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authorJason Evans <jasone@canonware.com>2011-04-01 03:36:17 (GMT)
committerJason Evans <jasone@canonware.com>2011-04-01 03:36:17 (GMT)
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- <xsl:import href="@XSLROOT@/html/docbook.xsl"/>
- <xsl:import href="@abs_srcroot@doc/stylesheet.xsl"/>
-</xsl:stylesheet>
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-<?xml version='1.0' encoding='UTF-8'?>
-<?xml-stylesheet type="text/xsl"
- href="http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl"?>
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
- "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
-]>
-
-<refentry>
- <refentryinfo>
- <title>User Manual</title>
- <productname>jemalloc</productname>
- <releaseinfo role="version">@jemalloc_version@</releaseinfo>
- <authorgroup>
- <author>
- <firstname>Jason</firstname>
- <surname>Evans</surname>
- <personblurb>Author</personblurb>
- </author>
- </authorgroup>
- </refentryinfo>
- <refmeta>
- <refentrytitle>JEMALLOC</refentrytitle>
- <manvolnum>3</manvolnum>
- </refmeta>
- <refnamediv>
- <refdescriptor>jemalloc</refdescriptor>
- <refname>jemalloc</refname>
- <!-- Each refname causes a man page file to be created. Only if this were
- the system malloc(3) implementation would these files be appropriate.
- <refname>malloc</refname>
- <refname>calloc</refname>
- <refname>posix_memalign</refname>
- <refname>realloc</refname>
- <refname>free</refname>
- <refname>malloc_usable_size</refname>
- <refname>malloc_stats_print</refname>
- <refname>mallctl</refname>
- <refname>mallctlnametomib</refname>
- <refname>mallctlbymib</refname>
- <refname>allocm</refname>
- <refname>rallocm</refname>
- <refname>sallocm</refname>
- <refname>dallocm</refname>
- -->
- <refpurpose>general purpose memory allocation functions</refpurpose>
- </refnamediv>
- <refsect1 id="library">
- <title>LIBRARY</title>
- <para>This manual describes jemalloc @jemalloc_version@. More information
- can be found at the <ulink
- url="http://www.canonware.com/jemalloc/">jemalloc website</ulink>.</para>
- </refsect1>
- <refsynopsisdiv>
- <title>SYNOPSIS</title>
- <funcsynopsis>
- <funcsynopsisinfo>#include &lt;<filename class="headerfile">stdlib.h</filename>&gt;
-#include &lt;<filename class="headerfile">jemalloc/jemalloc.h</filename>&gt;</funcsynopsisinfo>
- <refsect2>
- <title>Standard API</title>
- <funcprototype>
- <funcdef>void *<function>malloc</function></funcdef>
- <paramdef>size_t <parameter>size</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>void *<function>calloc</function></funcdef>
- <paramdef>size_t <parameter>number</parameter></paramdef>
- <paramdef>size_t <parameter>size</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>int <function>posix_memalign</function></funcdef>
- <paramdef>void **<parameter>ptr</parameter></paramdef>
- <paramdef>size_t <parameter>alignment</parameter></paramdef>
- <paramdef>size_t <parameter>size</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>void *<function>realloc</function></funcdef>
- <paramdef>void *<parameter>ptr</parameter></paramdef>
- <paramdef>size_t <parameter>size</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>void <function>free</function></funcdef>
- <paramdef>void *<parameter>ptr</parameter></paramdef>
- </funcprototype>
- </refsect2>
- <refsect2>
- <title>Non-standard API</title>
- <funcprototype>
- <funcdef>size_t <function>malloc_usable_size</function></funcdef>
- <paramdef>const void *<parameter>ptr</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>void <function>malloc_stats_print</function></funcdef>
- <paramdef>void <parameter>(*write_cb)</parameter>
- <funcparams>void *, const char *</funcparams>
- </paramdef>
- <paramdef>void *<parameter>cbopaque</parameter></paramdef>
- <paramdef>const char *<parameter>opts</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>int <function>mallctl</function></funcdef>
- <paramdef>const char *<parameter>name</parameter></paramdef>
- <paramdef>void *<parameter>oldp</parameter></paramdef>
- <paramdef>size_t *<parameter>oldlenp</parameter></paramdef>
- <paramdef>void *<parameter>newp</parameter></paramdef>
- <paramdef>size_t <parameter>newlen</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>int <function>mallctlnametomib</function></funcdef>
- <paramdef>const char *<parameter>name</parameter></paramdef>
- <paramdef>size_t *<parameter>mibp</parameter></paramdef>
- <paramdef>size_t *<parameter>miblenp</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>int <function>mallctlbymib</function></funcdef>
- <paramdef>const size_t *<parameter>mib</parameter></paramdef>
- <paramdef>size_t <parameter>miblen</parameter></paramdef>
- <paramdef>void *<parameter>oldp</parameter></paramdef>
- <paramdef>size_t *<parameter>oldlenp</parameter></paramdef>
- <paramdef>void *<parameter>newp</parameter></paramdef>
- <paramdef>size_t <parameter>newlen</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>void <function>(*malloc_message)</function></funcdef>
- <paramdef>void *<parameter>cbopaque</parameter></paramdef>
- <paramdef>const char *<parameter>s</parameter></paramdef>
- </funcprototype>
- <para><type>const char *</type><varname>malloc_conf</varname>;</para>
- </refsect2>
- <refsect2>
- <title>Experimental API</title>
- <funcprototype>
- <funcdef>int <function>allocm</function></funcdef>
- <paramdef>void **<parameter>ptr</parameter></paramdef>
- <paramdef>size_t *<parameter>rsize</parameter></paramdef>
- <paramdef>size_t <parameter>size</parameter></paramdef>
- <paramdef>int <parameter>flags</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>int <function>rallocm</function></funcdef>
- <paramdef>void **<parameter>ptr</parameter></paramdef>
- <paramdef>size_t *<parameter>rsize</parameter></paramdef>
- <paramdef>size_t <parameter>size</parameter></paramdef>
- <paramdef>size_t <parameter>extra</parameter></paramdef>
- <paramdef>int <parameter>flags</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>int <function>sallocm</function></funcdef>
- <paramdef>const void *<parameter>ptr</parameter></paramdef>
- <paramdef>size_t *<parameter>rsize</parameter></paramdef>
- <paramdef>int <parameter>flags</parameter></paramdef>
- </funcprototype>
- <funcprototype>
- <funcdef>int <function>dallocm</function></funcdef>
- <paramdef>void *<parameter>ptr</parameter></paramdef>
- <paramdef>int <parameter>flags</parameter></paramdef>
- </funcprototype>
- </refsect2>
- </funcsynopsis>
- </refsynopsisdiv>
- <refsect1 id="description">
- <title>DESCRIPTION</title>
- <refsect2>
- <title>Standard API</title>
-
- <para>The <function>malloc<parameter/></function> function allocates
- <parameter>size</parameter> bytes of uninitialized memory. The allocated
- space is suitably aligned (after possible pointer coercion) for storage
- of any type of object.</para>
-
- <para>The <function>calloc<parameter/></function> function allocates
- space for <parameter>number</parameter> objects, each
- <parameter>size</parameter> bytes in length. The result is identical to
- calling <function>malloc<parameter/></function> with an argument of
- <parameter>number</parameter> * <parameter>size</parameter>, with the
- exception that the allocated memory is explicitly initialized to zero
- bytes.</para>
-
- <para>The <function>posix_memalign<parameter/></function> function
- allocates <parameter>size</parameter> bytes of memory such that the
- allocation's base address is an even multiple of
- <parameter>alignment</parameter>, and returns the allocation in the value
- pointed to by <parameter>ptr</parameter>. The requested
- <parameter>alignment</parameter> must be a power of 2 at least as large
- as <code language="C">sizeof(<type>void *</type>)</code>.</para>
-
- <para>The <function>realloc<parameter/></function> function changes the
- size of the previously allocated memory referenced by
- <parameter>ptr</parameter> to <parameter>size</parameter> bytes. The
- contents of the memory are unchanged up to the lesser of the new and old
- sizes. If the new size is larger, the contents of the newly allocated
- portion of the memory are undefined. Upon success, the memory referenced
- by <parameter>ptr</parameter> is freed and a pointer to the newly
- allocated memory is returned. Note that
- <function>realloc<parameter/></function> may move the memory allocation,
- resulting in a different return value than <parameter>ptr</parameter>.
- If <parameter>ptr</parameter> is <constant>NULL</constant>, the
- <function>realloc<parameter/></function> function behaves identically to
- <function>malloc<parameter/></function> for the specified size.</para>
-
- <para>The <function>free<parameter/></function> function causes the
- allocated memory referenced by <parameter>ptr</parameter> to be made
- available for future allocations. If <parameter>ptr</parameter> is
- <constant>NULL</constant>, no action occurs.</para>
- </refsect2>
- <refsect2>
- <title>Non-standard API</title>
-
- <para>The <function>malloc_usable_size<parameter/></function> function
- returns the usable size of the allocation pointed to by
- <parameter>ptr</parameter>. The return value may be larger than the size
- that was requested during allocation. The
- <function>malloc_usable_size<parameter/></function> function is not a
- mechanism for in-place <function>realloc<parameter/></function>; rather
- it is provided solely as a tool for introspection purposes. Any
- discrepancy between the requested allocation size and the size reported
- by <function>malloc_usable_size<parameter/></function> should not be
- depended on, since such behavior is entirely implementation-dependent.
- </para>
-
- <para>The <function>malloc_stats_print<parameter/></function> function
- writes human-readable summary statistics via the
- <parameter>write_cb</parameter> callback function pointer and
- <parameter>cbopaque</parameter> data passed to
- <parameter>write_cb</parameter>, or
- <function>malloc_message<parameter/></function> if
- <parameter>write_cb</parameter> is <constant>NULL</constant>. This
- function can be called repeatedly. General information that never
- changes during execution can be omitted by specifying "g" as a character
- within the <parameter>opts</parameter> string. Note that
- <function>malloc_message<parameter/></function> uses the
- <function>mallctl*<parameter/></function> functions internally, so
- inconsistent statistics can be reported if multiple threads use these
- functions simultaneously. If <option>--enable-stats</option> is
- specified during configuration, &ldquo;m&rdquo; and &ldquo;a&rdquo; can
- be specified to omit merged arena and per arena statistics, respectively;
- &ldquo;b&rdquo; and &ldquo;l&rdquo; can be specified to omit per size
- class statistics for bins and large objects, respectively. Unrecognized
- characters are silently ignored. Note that thread caching may prevent
- some statistics from being completely up to date, since extra locking
- would be required to merge counters that track thread cache operations.
- </para>
-
- <para>The <function>mallctl<parameter/></function> function provides a
- general interface for introspecting the memory allocator, as well as
- setting modifiable parameters and triggering actions. The
- period-separated <parameter>name</parameter> argument specifies a
- location in a tree-structured namespace; see the <xref
- linkend="mallctl_namespace" xrefstyle="template:%t"/> section for
- documentation on the tree contents. To read a value, pass a pointer via
- <parameter>oldp</parameter> to adequate space to contain the value, and a
- pointer to its length via <parameter>oldlenp</parameter>; otherwise pass
- <constant>NULL</constant> and <constant>NULL</constant>. Similarly, to
- write a value, pass a pointer to the value via
- <parameter>newp</parameter>, and its length via
- <parameter>newlen</parameter>; otherwise pass <constant>NULL</constant>
- and <constant>0</constant>.</para>
-
- <para>The <function>mallctlnametomib<parameter/></function> function
- provides a way to avoid repeated name lookups for applications that
- repeatedly query the same portion of the namespace, by translating a name
- to a &ldquo;Management Information Base&rdquo; (MIB) that can be passed
- repeatedly to <function>mallctlbymib<parameter/></function>. Upon
- successful return from <function>mallctlnametomib<parameter/></function>,
- <parameter>mibp</parameter> contains an array of
- <parameter>*miblenp</parameter> integers, where
- <parameter>*miblenp</parameter> is the lesser of the number of components
- in <parameter>name</parameter> and the input value of
- <parameter>*miblenp</parameter>. Thus it is possible to pass a
- <parameter>*miblenp</parameter> that is smaller than the number of
- period-separated name components, which results in a partial MIB that can
- be used as the basis for constructing a complete MIB. For name
- components that are integers (e.g. the 2 in
- <link
- linkend="arenas.bin.i.size"><mallctl>arenas.bin.2.size</mallctl></link>),
- the corresponding MIB component will always be that integer. Therefore,
- it is legitimate to construct code like the following: <programlisting
- language="C"><![CDATA[
-unsigned nbins, i;
-
-int mib[4];
-size_t len, miblen;
-
-len = sizeof(nbins);
-mallctl("arenas.nbins", &nbins, &len, NULL, 0);
-
-miblen = 4;
-mallnametomib("arenas.bin.0.size", mib, &miblen);
-for (i = 0; i < nbins; i++) {
- size_t bin_size;
-
- mib[2] = i;
- len = sizeof(bin_size);
- mallctlbymib(mib, miblen, &bin_size, &len, NULL, 0);
- /* Do something with bin_size... */
-}]]></programlisting></para>
- </refsect2>
- <refsect2>
- <title>Experimental API</title>
- <para>The experimental API is subject to change or removal without regard
- for backward compatibility.</para>
-
- <para>The <function>allocm<parameter/></function>,
- <function>rallocm<parameter/></function>,
- <function>sallocm<parameter/></function>, and
- <function>dallocm<parameter/></function> functions all have a
- <parameter>flags</parameter> argument that can be used to specify
- options. The functions only check the options that are contextually
- relevant. Use bitwise or (<code language="C">|</code>) operations to
- specify one or more of the following:
- <variablelist>
- <varlistentry>
- <term><constant>ALLOCM_LG_ALIGN(<parameter>la</parameter>)
- </constant></term>
-
- <listitem><para>Align the memory allocation to start at an address
- that is a multiple of <code language="C">(1 &lt;&lt;
- <parameter>la</parameter>)</code>. This macro does not validate
- that <parameter>la</parameter> is within the valid
- range.</para></listitem>
- </varlistentry>
- <varlistentry>
- <term><constant>ALLOCM_ALIGN(<parameter>a</parameter>)
- </constant></term>
-
- <listitem><para>Align the memory allocation to start at an address
- that is a multiple of <parameter>a</parameter>, where
- <parameter>a</parameter> is a power of two. This macro does not
- validate that <parameter>a</parameter> is a power of 2.
- </para></listitem>
- </varlistentry>
- <varlistentry>
- <term><constant>ALLOCM_ZERO</constant></term>
-
- <listitem><para>Initialize newly allocated memory to contain zero
- bytes. In the growing reallocation case, the real size prior to
- reallocation defines the boundary between untouched bytes and those
- that are initialized to contain zero bytes. If this option is
- absent, newly allocated memory is uninitialized.</para></listitem>
- </varlistentry>
- <varlistentry>
- <term><constant>ALLOCM_NO_MOVE</constant></term>
-
- <listitem><para>For reallocation, fail rather than moving the
- object. This constraint can apply to both growth and
- shrinkage.</para></listitem>
- </varlistentry>
- </variablelist>
- </para>
-
- <para>The <function>allocm<parameter/></function> function allocates at
- least <parameter>size</parameter> bytes of memory, sets
- <parameter>*ptr</parameter> to the base address of the allocation, and
- sets <parameter>*rsize</parameter> to the real size of the allocation if
- <parameter>rsize</parameter> is not <constant>NULL</constant>.</para>
-
- <para>The <function>rallocm<parameter/></function> function resizes the
- allocation at <parameter>*ptr</parameter> to be at least
- <parameter>size</parameter> bytes, sets <parameter>*ptr</parameter> to
- the base address of the allocation if it moved, and sets
- <parameter>*rsize</parameter> to the real size of the allocation if
- <parameter>rsize</parameter> is not <constant>NULL</constant>. If
- <parameter>extra</parameter> is non-zero, an attempt is made to resize
- the allocation to be at least <code
- language="C"><parameter>size</parameter> +
- <parameter>extra</parameter>)</code> bytes, though inability to allocate
- the extra byte(s) will not by itself result in failure. Behavior is
- undefined if <code language="C">(<parameter>size</parameter> +
- <parameter>extra</parameter> &gt;
- <constant>SIZE_T_MAX</constant>)</code>.</para>
-
- <para>The <function>sallocm<parameter/></function> function sets
- <parameter>*rsize</parameter> to the real size of the allocation.</para>
-
- <para>The <function>dallocm<parameter/></function> function causes the
- memory referenced by <parameter>ptr</parameter> to be made available for
- future allocations.</para>
- </refsect2>
- </refsect1>
- <refsect1 id="tuning">
- <title>TUNING</title>
- <para>Once, when the first call is made to one of the memory allocation
- routines, the allocator initializes its internals based in part on various
- options that can be specified at compile- or run-time.</para>
-
- <para>The string pointed to by the global variable
- <varname>malloc_conf</varname>, the &ldquo;name&rdquo; of the file
- referenced by the symbolic link named <filename
- class="symlink">/etc/malloc.conf</filename>, and the value of the
- environment variable <envar>MALLOC_CONF</envar>, will be interpreted, in
- that order, from left to right as options.</para>
-
- <para>An options string is a comma-separated list of option:value pairs.
- There is one key corresponding to each <link
- linkend="opt.abort"><mallctl>opt.*</mallctl></link> mallctl (see the <xref
- linkend="mallctl_namespace" xrefstyle="template:%t"/> section for options
- documentation). For example, <literal>abort:true,narenas:1</literal> sets
- the <link linkend="opt.abort"><mallctl>opt.abort</mallctl></link> and <link
- linkend="opt.narenas"><mallctl>opt.narenas</mallctl></link> options. Some
- options have boolean values (true/false), others have integer values (base
- 8, 10, or 16, depending on prefix), and yet others have raw string
- values.</para>
- </refsect1>
- <refsect1 id="implementation_notes">
- <title>IMPLEMENTATION NOTES</title>
- <para>Traditionally, allocators have used
- <citerefentry><refentrytitle>sbrk</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> to obtain memory, which is
- suboptimal for several reasons, including race conditions, increased
- fragmentation, and artificial limitations on maximum usable memory. If
- <option>--enable-dss</option> is specified during configuration, this
- allocator uses both <citerefentry><refentrytitle>sbrk</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> and
- <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry>, in that order of preference;
- otherwise only <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> is used.</para>
-
- <para>This allocator uses multiple arenas in order to reduce lock
- contention for threaded programs on multi-processor systems. This works
- well with regard to threading scalability, but incurs some costs. There is
- a small fixed per-arena overhead, and additionally, arenas manage memory
- completely independently of each other, which means a small fixed increase
- in overall memory fragmentation. These overheads are not generally an
- issue, given the number of arenas normally used. Note that using
- substantially more arenas than the default is not likely to improve
- performance, mainly due to reduced cache performance. However, it may make
- sense to reduce the number of arenas if an application does not make much
- use of the allocation functions.</para>
-
- <para>In addition to multiple arenas, unless
- <option>--disable-tcache</option> is specified during configuration, this
- allocator supports thread-specific caching for small and large objects, in
- order to make it possible to completely avoid synchronization for most
- allocation requests. Such caching allows very fast allocation in the
- common case, but it increases memory usage and fragmentation, since a
- bounded number of objects can remain allocated in each thread cache.</para>
-
- <para>Memory is conceptually broken into equal-sized chunks, where the
- chunk size is a power of two that is greater than the page size. Chunks
- are always aligned to multiples of the chunk size. This alignment makes it
- possible to find metadata for user objects very quickly.</para>
-
- <para>User objects are broken into three categories according to size:
- small, large, and huge. Small objects are smaller than one page. Large
- objects are smaller than the chunk size. Huge objects are a multiple of
- the chunk size. Small and large objects are managed by arenas; huge
- objects are managed separately in a single data structure that is shared by
- all threads. Huge objects are used by applications infrequently enough
- that this single data structure is not a scalability issue.</para>
-
- <para>Each chunk that is managed by an arena tracks its contents as runs of
- contiguous pages (unused, backing a set of small objects, or backing one
- large object). The combination of chunk alignment and chunk page maps
- makes it possible to determine all metadata regarding small and large
- allocations in constant time.</para>
-
- <para>Small objects are managed in groups by page runs. Each run maintains
- a frontier and free list to track which regions are in use. Unless
- <option>--disable-tiny</option> is specified during configuration,
- allocation requests that are no more than half the quantum (8 or 16,
- depending on architecture) are rounded up to the nearest power of two that
- is at least <code language="C">sizeof(<type>void *</type>)</code>.
- Allocation requests that are more than half the quantum, but no more than
- the minimum cacheline-multiple size class (see the <link
- linkend="opt.lg_qspace_max"><mallctl>opt.lg_qspace_max</mallctl></link>
- option) are rounded up to the nearest multiple of the quantum. Allocation
- requests that are more than the minimum cacheline-multiple size class, but
- no more than the minimum subpage-multiple size class (see the <link
- linkend="opt.lg_cspace_max"><mallctl>opt.lg_cspace_max</mallctl></link>
- option) are rounded up to the nearest multiple of the cacheline size (64).
- Allocation requests that are more than the minimum subpage-multiple size
- class, but no more than the maximum subpage-multiple size class are rounded
- up to the nearest multiple of the subpage size (256). Allocation requests
- that are more than the maximum subpage-multiple size class, but small
- enough to fit in an arena-managed chunk (see the <link
- linkend="opt.lg_chunk"><mallctl>opt.lg_chunk</mallctl></link> option), are
- rounded up to the nearest run size. Allocation requests that are too large
- to fit in an arena-managed chunk are rounded up to the nearest multiple of
- the chunk size.</para>
-
- <para>Allocations are packed tightly together, which can be an issue for
- multi-threaded applications. If you need to assure that allocations do not
- suffer from cacheline sharing, round your allocation requests up to the
- nearest multiple of the cacheline size, or specify cacheline alignment when
- allocating.</para>
-
- <para>Assuming 4 MiB chunks, 4 KiB pages, and a 16-byte quantum on a 64-bit
- system, the size classes in each category are as shown in <xref
- linkend="size_classes" xrefstyle="template:Table %n"/>.</para>
-
- <table xml:id="size_classes" frame="all">
- <title>Size classes</title>
- <tgroup cols="3" align="left" colsep="1" rowsep="1">
- <colspec colname="c1"/>
- <colspec colname="c2"/>
- <colspec colname="c3"/>
- <thead>
- <row>
- <entry>Category</entry>
- <entry>Subcategory</entry>
- <entry>Size</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry morerows="3">Small</entry>
- <entry>Tiny</entry>
- <entry>[8]</entry>
- </row>
- <row>
- <entry>Quantum-spaced</entry>
- <entry>[16, 32, 48, ..., 128]</entry>
- </row>
- <row>
- <entry>Cacheline-spaced</entry>
- <entry>[192, 256, 320, ..., 512]</entry>
- </row>
- <row>
- <entry>Subpage-spaced</entry>
- <entry>[768, 1024, 1280, ..., 3840]</entry>
- </row>
- <row>
- <entry namest="c1" nameend="c2">Large</entry>
- <entry>[4 KiB, 8 KiB, 12 KiB, ..., 4072 KiB]</entry>
- </row>
- <row>
- <entry namest="c1" nameend="c2">Huge</entry>
- <entry>[4 MiB, 8 MiB, 12 MiB, ...]</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
- </refsect1>
- <refsect1 id="mallctl_namespace">
- <title>MALLCTL NAMESPACE</title>
- <para>The following names are defined in the namespace accessible via the
- <function>mallctl*<parameter/></function> functions. Value types are
- specified in parentheses, their readable/writable statuses are encoded as
- <literal>rw</literal>, <literal>r-</literal>, <literal>-w</literal>, or
- <literal>--</literal>, and required build configuration flags follow, if
- any. A name element encoded as <literal>&lt;i&gt;</literal> or
- <literal>&lt;j&gt;</literal> indicates an integer component, where the
- integer varies from 0 to some upper value that must be determined via
- introspection. In the case of <mallctl>stats.arenas.&lt;i&gt;.*</mallctl>,
- <literal>&lt;i&gt;</literal> equal to <link
- linkend="arenas.narenas"><mallctl>arenas.narenas</mallctl></link> can be
- used to access the summation of statistics from all arenas. Take special
- note of the <link linkend="epoch"><mallctl>epoch</mallctl></link> mallctl,
- which controls refreshing of cached dynamic statistics.</para>
-
- <variablelist>
- <varlistentry>
- <term>
- <mallctl>version</mallctl>
- (<type>const char *</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Return the jemalloc version string.</para></listitem>
- </varlistentry>
-
- <varlistentry id="epoch">
- <term>
- <mallctl>epoch</mallctl>
- (<type>uint64_t</type>)
- <literal>rw</literal>
- </term>
- <listitem><para>If a value is passed in, refresh the data from which
- the <function>mallctl*<parameter/></function> functions report values,
- and increment the epoch. Return the current epoch. This is useful for
- detecting whether another thread caused a refresh.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.debug</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-debug</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.dss</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-dss</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.dynamic_page_shift</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-dynamic-page-shift</option> was
- specified during build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.fill</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-fill</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.lazy_lock</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-lazy-lock</option> was specified
- during build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.prof</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-prof</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.prof_libgcc</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--disable-prof-libgcc</option> was not
- specified during build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.prof_libunwind</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-prof-libunwind</option> was specified
- during build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.stats</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-stats</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.swap</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-swap</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.sysv</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-sysv</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.tcache</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--disable-tcache</option> was not specified
- during build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.tiny</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--disable-tiny</option> was not specified
- during build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.tls</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--disable-tls</option> was not specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>config.xmalloc</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para><option>--enable-xmalloc</option> was specified during
- build configuration.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.abort">
- <term>
- <mallctl>opt.abort</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Abort-on-warning enabled/disabled. If true, most
- warnings are fatal. The process will call
- <citerefentry><refentrytitle>abort</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry> in these cases. This option is
- disabled by default unless <option>--enable-debug</option> is
- specified during configuration, in which case it is enabled by default.
- </para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_qspace_max">
- <term>
- <mallctl>opt.lg_qspace_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Size (log base 2) of the maximum size class that is a
- multiple of the quantum (8 or 16 bytes, depending on architecture).
- Above this size, cacheline spacing is used for size classes. The
- default value is 128 bytes (2^7).</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_cspace_max">
- <term>
- <mallctl>opt.lg_cspace_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Size (log base 2) of the maximum size class that is a
- multiple of the cacheline size (64). Above this size, subpage spacing
- (256 bytes) is used for size classes. The default value is 512 bytes
- (2^9).</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_chunk">
- <term>
- <mallctl>opt.lg_chunk</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Virtual memory chunk size (log base 2). The default
- chunk size is 4 MiB (2^22).</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.narenas">
- <term>
- <mallctl>opt.narenas</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum number of arenas to use. The default maximum
- number of arenas is four times the number of CPUs, or one if there is a
- single CPU.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_dirty_mult">
- <term>
- <mallctl>opt.lg_dirty_mult</mallctl>
- (<type>ssize_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Per-arena minimum ratio (log base 2) of active to dirty
- pages. Some dirty unused pages may be allowed to accumulate, within
- the limit set by the ratio (or one chunk worth of dirty pages,
- whichever is greater), before informing the kernel about some of those
- pages via <citerefentry><refentrytitle>madvise</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> or a similar system call. This
- provides the kernel with sufficient information to recycle dirty pages
- if physical memory becomes scarce and the pages remain unused. The
- default minimum ratio is 32:1 (2^5:1); an option value of -1 will
- disable dirty page purging.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.stats_print">
- <term>
- <mallctl>opt.stats_print</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Enable/disable statistics printing at exit. If
- enabled, the <function>malloc_stats_print<parameter/></function>
- function is called at program exit via an
- <citerefentry><refentrytitle>atexit</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry> function. If
- <option>--enable-stats</option> is specified during configuration, this
- has the potential to cause deadlock for a multi-threaded process that
- exits while one or more threads are executing in the memory allocation
- functions. Therefore, this option should only be used with care; it is
- primarily intended as a performance tuning aid during application
- development. This option is disabled by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.junk">
- <term>
- <mallctl>opt.junk</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-fill</option>]
- </term>
- <listitem><para>Junk filling enabled/disabled. If enabled, each byte
- of uninitialized allocated memory will be initialized to
- <literal>0xa5</literal>. All deallocated memory will be initialized to
- <literal>0x5a</literal>. This is intended for debugging and will
- impact performance negatively. This option is disabled by default
- unless <option>--enable-debug</option> is specified during
- configuration, in which case it is enabled by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.zero">
- <term>
- <mallctl>opt.zero</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-fill</option>]
- </term>
- <listitem><para>Zero filling enabled/disabled. If enabled, each byte
- of uninitialized allocated memory will be initialized to 0. Note that
- this initialization only happens once for each byte, so
- <function>realloc<parameter/></function> and
- <function>rallocm<parameter/></function> calls do not zero memory that
- was previously allocated. This is intended for debugging and will
- impact performance negatively. This option is disabled by default.
- </para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.sysv">
- <term>
- <mallctl>opt.sysv</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-sysv</option>]
- </term>
- <listitem><para>If enabled, attempting to allocate zero bytes will
- return a <constant>NULL</constant> pointer instead of a valid pointer.
- (The default behavior is to make a minimal allocation and return a
- pointer to it.) This option is provided for System V compatibility.
- This option is incompatible with the <link
- linkend="opt.xmalloc"><mallctl>opt.xmalloc</mallctl></link> option.
- This option is disabled by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.xmalloc">
- <term>
- <mallctl>opt.xmalloc</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-xmalloc</option>]
- </term>
- <listitem><para>Abort-on-out-of-memory enabled/disabled. If enabled,
- rather than returning failure for any allocation function, display a
- diagnostic message on <constant>STDERR_FILENO</constant> and cause the
- program to drop core (using
- <citerefentry><refentrytitle>abort</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry>). If an application is
- designed to depend on this behavior, set the option at compile time by
- including the following in the source code:
- <programlisting language="C"><![CDATA[
-malloc_conf = "xmalloc:true";]]></programlisting>
- This option is disabled by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.tcache">
- <term>
- <mallctl>opt.tcache</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-tcache</option>]
- </term>
- <listitem><para>Thread-specific caching enabled/disabled. When there
- are multiple threads, each thread uses a thread-specific cache for
- objects up to a certain size. Thread-specific caching allows many
- allocations to be satisfied without performing any thread
- synchronization, at the cost of increased memory use. See the
- <link
- linkend="opt.lg_tcache_gc_sweep"><mallctl>opt.lg_tcache_gc_sweep</mallctl></link>
- and <link
- linkend="opt.lg_tcache_max"><mallctl>opt.lg_tcache_max</mallctl></link>
- options for related tuning information. This option is enabled by
- default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_tcache_gc_sweep">
- <term>
- <mallctl>opt.lg_tcache_gc_sweep</mallctl>
- (<type>ssize_t</type>)
- <literal>r-</literal>
- [<option>--enable-tcache</option>]
- </term>
- <listitem><para>Approximate interval (log base 2) between full
- thread-specific cache garbage collection sweeps, counted in terms of
- thread-specific cache allocation/deallocation events. Garbage
- collection is actually performed incrementally, one size class at a
- time, in order to avoid large collection pauses. The default sweep
- interval is 8192 (2^13); setting this option to -1 will disable garbage
- collection.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_tcache_max">
- <term>
- <mallctl>opt.lg_tcache_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-tcache</option>]
- </term>
- <listitem><para>Maximum size class (log base 2) to cache in the
- thread-specific cache. At a minimum, all small size classes are
- cached, and at a maximum all large size classes are cached. The
- default maximum is 32 KiB (2^15).</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.prof">
- <term>
- <mallctl>opt.prof</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Memory profiling enabled/disabled. If enabled, profile
- memory allocation activity, and use an
- <citerefentry><refentrytitle>atexit</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry> function to dump final memory
- usage to a file named according to the pattern
- <filename>&lt;prefix&gt;.&lt;pid&gt;.&lt;seq&gt;.f.heap</filename>,
- where <literal>&lt;prefix&gt;</literal> is controlled by the <link
- linkend="opt.prof_prefix"><mallctl>opt.prof_prefix</mallctl></link>
- option. See the <link
- linkend="opt.lg_prof_bt_max"><mallctl>opt.lg_prof_bt_max</mallctl></link>
- option for backtrace depth control. See the <link
- linkend="opt.prof_active"><mallctl>opt.prof_active</mallctl></link>
- option for on-the-fly activation/deactivation. See the <link
- linkend="opt.lg_prof_sample"><mallctl>opt.lg_prof_sample</mallctl></link>
- option for probabilistic sampling control. See the <link
- linkend="opt.prof_accum"><mallctl>opt.prof_accum</mallctl></link>
- option for control of cumulative sample reporting. See the <link
- linkend="opt.lg_prof_tcmax"><mallctl>opt.lg_prof_tcmax</mallctl></link>
- option for control of per thread backtrace caching. See the <link
- linkend="opt.lg_prof_interval"><mallctl>opt.lg_prof_interval</mallctl></link>
- option for information on interval-triggered profile dumping, and the
- <link linkend="opt.prof_gdump"><mallctl>opt.prof_gdump</mallctl></link>
- option for information on high-water-triggered profile dumping.
- Profile output is compatible with the included <command>pprof</command>
- Perl script, which originates from the <ulink
- url="http://code.google.com/p/google-perftools/">google-perftools
- package</ulink>.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.prof_prefix">
- <term>
- <mallctl>opt.prof_prefix</mallctl>
- (<type>const char *</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Filename prefix for profile dumps. If the prefix is
- set to the empty string, no automatic dumps will occur; this is
- primarily useful for disabling the automatic final heap dump (which
- also disables leak reporting, if enabled). The default prefix is
- <filename>jeprof</filename>.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_prof_bt_max">
- <term>
- <mallctl>opt.lg_prof_bt_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Maximum backtrace depth (log base 2) when profiling
- memory allocation activity. The default is 128 (2^7).</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.prof_active">
- <term>
- <mallctl>opt.prof_active</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Profiling activated/deactivated. This is a secondary
- control mechanism that makes it possible to start the application with
- profiling enabled (see the <link
- linkend="opt.prof"><mallctl>opt.prof</mallctl></link> option) but
- inactive, then toggle profiling at any time during program execution
- with the <link
- linkend="prof.active"><mallctl>prof.active</mallctl></link> mallctl.
- This option is enabled by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_prof_sample">
- <term>
- <mallctl>opt.lg_prof_sample</mallctl>
- (<type>ssize_t</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Average interval (log base 2) between allocation
- samples, as measured in bytes of allocation activity. Increasing the
- sampling interval decreases profile fidelity, but also decreases the
- computational overhead. The default sample interval is 1 (2^0) (i.e.
- all allocations are sampled).</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.prof_accum">
- <term>
- <mallctl>opt.prof_accum</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Reporting of cumulative object/byte counts in profile
- dumps enabled/disabled. If this option is enabled, every unique
- backtrace must be stored for the duration of execution. Depending on
- the application, this can impose a large memory overhead, and the
- cumulative counts are not always of interest. See the
- <link
- linkend="opt.lg_prof_tcmax"><mallctl>opt.lg_prof_tcmax</mallctl></link>
- option for control of per thread backtrace caching, which has important
- interactions. This option is enabled by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_prof_tcmax">
- <term>
- <mallctl>opt.lg_prof_tcmax</mallctl>
- (<type>ssize_t</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Maximum per thread backtrace cache (log base 2) used
- for heap profiling. A backtrace can only be discarded if the
- <link linkend="opt.prof_accum"><mallctl>opt.prof_accum</mallctl></link>
- option is disabled, and no thread caches currently refer to the
- backtrace. Therefore, a backtrace cache limit should be imposed if the
- intention is to limit how much memory is used by backtraces. By
- default, no limit is imposed (encoded as -1).
- </para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.lg_prof_interval">
- <term>
- <mallctl>opt.lg_prof_interval</mallctl>
- (<type>ssize_t</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Average interval (log base 2) between memory profile
- dumps, as measured in bytes of allocation activity. The actual
- interval between dumps may be sporadic because decentralized allocation
- counters are used to avoid synchronization bottlenecks. Profiles are
- dumped to files named according to the pattern
- <filename>&lt;prefix&gt;.&lt;pid&gt;.&lt;seq&gt;.i&lt;iseq&gt;.heap</filename>,
- where <literal>&lt;prefix&gt;</literal> is controlled by the
- <link
- linkend="opt.prof_prefix"><mallctl>opt.prof_prefix</mallctl></link>
- option. By default, interval-triggered profile dumping is disabled
- (encoded as -1).
- </para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.prof_gdump">
- <term>
- <mallctl>opt.prof_gdump</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Trigger a memory profile dump every time the total
- virtual memory exceeds the previous maximum. Profiles are dumped to
- files named according to the pattern
- <filename>&lt;prefix&gt;.&lt;pid&gt;.&lt;seq&gt;.u&lt;useq&gt;.heap</filename>,
- where <literal>&lt;prefix&gt;</literal> is controlled by the <link
- linkend="opt.prof_prefix"><mallctl>opt.prof_prefix</mallctl></link>
- option. This option is disabled by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.prof_leak">
- <term>
- <mallctl>opt.prof_leak</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Leak reporting enabled/disabled. If enabled, use an
- <citerefentry><refentrytitle>atexit</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry> function to report memory leaks
- detected by allocation sampling. See the
- <link
- linkend="opt.lg_prof_bt_max"><mallctl>opt.lg_prof_bt_max</mallctl></link>
- option for backtrace depth control. See the
- <link linkend="opt.prof"><mallctl>opt.prof</mallctl></link> option for
- information on analyzing heap profile output. This option is disabled
- by default.</para></listitem>
- </varlistentry>
-
- <varlistentry id="opt.overcommit">
- <term>
- <mallctl>opt.overcommit</mallctl>
- (<type>bool</type>)
- <literal>r-</literal>
- [<option>--enable-swap</option>]
- </term>
- <listitem><para>Over-commit enabled/disabled. If enabled, over-commit
- memory as a side effect of using anonymous
- <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> or
- <citerefentry><refentrytitle>sbrk</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> for virtual memory allocation.
- In order for overcommit to be disabled, the <link
- linkend="swap.fds"><mallctl>swap.fds</mallctl></link> mallctl must have
- been successfully written to. This option is enabled by
- default.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>tcache.flush</mallctl>
- (<type>void</type>)
- <literal>--</literal>
- [<option>--enable-tcache</option>]
- </term>
- <listitem><para>Flush calling thread's tcache. This interface releases
- all cached objects and internal data structures associated with the
- calling thread's thread-specific cache. Ordinarily, this interface
- need not be called, since automatic periodic incremental garbage
- collection occurs, and the thread cache is automatically discarded when
- a thread exits. However, garbage collection is triggered by allocation
- activity, so it is possible for a thread that stops
- allocating/deallocating to retain its cache indefinitely, in which case
- the developer may find manual flushing useful.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>thread.arena</mallctl>
- (<type>unsigned</type>)
- <literal>rw</literal>
- </term>
- <listitem><para>Get or set the arena associated with the calling
- thread. The arena index must be less than the maximum number of arenas
- (see the <link
- linkend="arenas.narenas"><mallctl>arenas.narenas</mallctl></link>
- mallctl). If the specified arena was not initialized beforehand (see
- the <link
- linkend="arenas.initialized"><mallctl>arenas.initialized</mallctl></link>
- mallctl), it will be automatically initialized as a side effect of
- calling this interface.</para></listitem>
- </varlistentry>
-
- <varlistentry id="thread.allocated">
- <term>
- <mallctl>thread.allocated</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Get the total number of bytes ever allocated by the
- calling thread. This counter has the potential to wrap around; it is
- up to the application to appropriately interpret the counter in such
- cases.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>thread.allocatedp</mallctl>
- (<type>uint64_t *</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Get a pointer to the the value that is returned by the
- <link
- linkend="thread.allocated"><mallctl>thread.allocated</mallctl></link>
- mallctl. This is useful for avoiding the overhead of repeated
- <function>mallctl*<parameter/></function> calls.</para></listitem>
- </varlistentry>
-
- <varlistentry id="thread.deallocated">
- <term>
- <mallctl>thread.deallocated</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Get the total number of bytes ever deallocated by the
- calling thread. This counter has the potential to wrap around; it is
- up to the application to appropriately interpret the counter in such
- cases.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>thread.deallocatedp</mallctl>
- (<type>uint64_t *</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Get a pointer to the the value that is returned by the
- <link
- linkend="thread.deallocated"><mallctl>thread.deallocated</mallctl></link>
- mallctl. This is useful for avoiding the overhead of repeated
- <function>mallctl*<parameter/></function> calls.</para></listitem>
- </varlistentry>
-
- <varlistentry id="arenas.narenas">
- <term>
- <mallctl>arenas.narenas</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum number of arenas.</para></listitem>
- </varlistentry>
-
- <varlistentry id="arenas.initialized">
- <term>
- <mallctl>arenas.initialized</mallctl>
- (<type>bool *</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>An array of <link
- linkend="arenas.narenas"><mallctl>arenas.narenas</mallctl></link>
- booleans. Each boolean indicates whether the corresponding arena is
- initialized.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.quantum</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Quantum size.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.cacheline</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Assumed cacheline size.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.subpage</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Subpage size class interval.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.pagesize</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Page size.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.chunksize</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Chunk size.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.tspace_min</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Minimum tiny size class. Tiny size classes are powers
- of two.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.tspace_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum tiny size class. Tiny size classes are powers
- of two.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.qspace_min</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Minimum quantum-spaced size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.qspace_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum quantum-spaced size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.cspace_min</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Minimum cacheline-spaced size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.cspace_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum cacheline-spaced size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.sspace_min</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Minimum subpage-spaced size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.sspace_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum subpage-spaced size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.tcache_max</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-tcache</option>]
- </term>
- <listitem><para>Maximum thread-cached size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.ntbins</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of tiny bin size classes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.nqbins</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of quantum-spaced bin size
- classes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.ncbins</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of cacheline-spaced bin size
- classes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.nsbins</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of subpage-spaced bin size
- classes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.nbins</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Total number of bin size classes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.nhbins</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- [<option>--enable-tcache</option>]
- </term>
- <listitem><para>Total number of thread cache bin size
- classes.</para></listitem>
- </varlistentry>
-
- <varlistentry id="arenas.bin.i.size">
- <term>
- <mallctl>arenas.bin.&lt;i&gt;.size</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum size supported by size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.bin.&lt;i&gt;.nregs</mallctl>
- (<type>uint32_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of regions per page run.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.bin.&lt;i&gt;.run_size</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of bytes per page run.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.nlruns</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Total number of large size classes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.lrun.&lt;i&gt;.size</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Maximum size supported by this large size
- class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>arenas.purge</mallctl>
- (<type>unsigned</type>)
- <literal>-w</literal>
- </term>
- <listitem><para>Purge unused dirty pages for the specified arena, or
- for all arenas if none is specified.</para></listitem>
- </varlistentry>
-
- <varlistentry id="prof.active">
- <term>
- <mallctl>prof.active</mallctl>
- (<type>bool</type>)
- <literal>rw</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Control whether sampling is currently active. See the
- <link
- linkend="opt.prof_active"><mallctl>opt.prof_active</mallctl></link>
- option for additional information.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>prof.dump</mallctl>
- (<type>const char *</type>)
- <literal>-w</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Dump a memory profile to the specified file, or if NULL
- is specified, to a file according to the pattern
- <filename>&lt;prefix&gt;.&lt;pid&gt;.&lt;seq&gt;.m&lt;mseq&gt;.heap</filename>,
- where <literal>&lt;prefix&gt;</literal> is controlled by the
- <link
- linkend="opt.prof_prefix"><mallctl>opt.prof_prefix</mallctl></link>
- option.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>prof.interval</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-prof</option>]
- </term>
- <listitem><para>Average number of bytes allocated between
- inverval-based profile dumps. See the
- <link
- linkend="opt.lg_prof_interval"><mallctl>opt.lg_prof_interval</mallctl></link>
- option for additional information.</para></listitem>
- </varlistentry>
-
- <varlistentry id="stats.cactive">
- <term>
- <mallctl>stats.cactive</mallctl>
- (<type>size_t *</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Pointer to a counter that contains an approximate count
- of the current number of bytes in active pages. The estimate may be
- high, but never low, because each arena rounds up to the nearest
- multiple of the chunk size when computing its contribution to the
- counter. Note that the <link
- linkend="epoch"><mallctl>epoch</mallctl></link> mallctl has no bearing
- on this counter. Furthermore, counter consistency is maintained via
- atomic operations, so it is necessary to use an atomic operation in
- order to guarantee a consistent read when dereferencing the pointer.
- </para></listitem>
- </varlistentry>
-
- <varlistentry id="stats.allocated">
- <term>
- <mallctl>stats.allocated</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Total number of bytes allocated by the
- application.</para></listitem>
- </varlistentry>
-
- <varlistentry id="stats.active">
- <term>
- <mallctl>stats.active</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Total number of bytes in active pages allocated by the
- application. This is a multiple of the page size, and greater than or
- equal to <link
- linkend="stats.allocated"><mallctl>stats.allocated</mallctl></link>.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.mapped</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Total number of bytes in chunks mapped on behalf of the
- application. This is a multiple of the chunk size, and is at least as
- large as <link
- linkend="stats.active"><mallctl>stats.active</mallctl></link>. This
- does not include inactive chunks backed by swap files. his does not
- include inactive chunks embedded in the DSS.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.chunks.current</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Total number of chunks actively mapped on behalf of the
- application. This does not include inactive chunks backed by swap
- files. This does not include inactive chunks embedded in the DSS.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.chunks.total</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of chunks allocated.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.chunks.high</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Maximum number of active chunks at any time thus far.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.huge.allocated</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Number of bytes currently allocated by huge objects.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.huge.nmalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of huge allocation requests.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.huge.ndalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of huge deallocation requests.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.nthreads</mallctl>
- (<type>unsigned</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of threads currently assigned to
- arena.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.pactive</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of pages in active runs.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.pdirty</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- </term>
- <listitem><para>Number of pages within unused runs that are potentially
- dirty, and for which <function>madvise<parameter>...</parameter>
- <parameter><constant>MADV_DONTNEED</constant></parameter></function> or
- similar has not been called.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.mapped</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Number of mapped bytes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.npurge</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Number of dirty page purge sweeps performed.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.nmadvise</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Number of <function>madvise<parameter>...</parameter>
- <parameter><constant>MADV_DONTNEED</constant></parameter></function> or
- similar calls made to purge dirty pages.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.npurged</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Number of pages purged.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.small.allocated</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Number of bytes currently allocated by small objects.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.small.nmalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of allocation requests served by
- small bins.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.small.ndalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of small objects returned to bins.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.small.nrequests</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of small allocation requests.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.large.allocated</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Number of bytes currently allocated by large objects.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.large.nmalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of large allocation requests served
- directly by the arena.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.large.ndalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of large deallocation requests served
- directly by the arena.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.large.nrequests</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of large allocation requests.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.allocated</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Current number of bytes allocated by
- bin.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.nmalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of allocations served by bin.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.ndalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of allocations returned to bin.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.nrequests</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of allocation
- requests.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.nfills</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option> <option>--enable-tcache</option>]
- </term>
- <listitem><para>Cumulative number of tcache fills.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.nflushes</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option> <option>--enable-tcache</option>]
- </term>
- <listitem><para>Cumulative number of tcache flushes.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.nruns</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of runs created.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.nreruns</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of times the current run from which
- to allocate changed.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.highruns</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Maximum number of runs at any time thus far.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.bins.&lt;j&gt;.curruns</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Current number of runs.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.lruns.&lt;j&gt;.nmalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of allocation requests for this size
- class served directly by the arena.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.lruns.&lt;j&gt;.ndalloc</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of deallocation requests for this
- size class served directly by the arena.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.lruns.&lt;j&gt;.nrequests</mallctl>
- (<type>uint64_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Cumulative number of allocation requests for this size
- class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.lruns.&lt;j&gt;.highruns</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Maximum number of runs at any time thus far for this
- size class.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>stats.arenas.&lt;i&gt;.lruns.&lt;j&gt;.curruns</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats</option>]
- </term>
- <listitem><para>Current number of runs for this size class.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>swap.avail</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats --enable-swap</option>]
- </term>
- <listitem><para>Number of swap file bytes that are currently not
- associated with any chunk (i.e. mapped, but otherwise completely
- unmanaged).</para></listitem>
- </varlistentry>
-
- <varlistentry id="swap.prezeroed">
- <term>
- <mallctl>swap.prezeroed</mallctl>
- (<type>bool</type>)
- <literal>rw</literal>
- [<option>--enable-swap</option>]
- </term>
- <listitem><para>If true, the allocator assumes that the swap file(s)
- contain nothing but nil bytes. If this assumption is violated,
- allocator behavior is undefined. This value becomes read-only after
- <link linkend="swap.fds"><mallctl>swap.fds</mallctl></link> is
- successfully written to.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>swap.nfds</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-swap</option>]
- </term>
- <listitem><para>Number of file descriptors in use for swap.
- </para></listitem>
- </varlistentry>
-
- <varlistentry id="swap.fds">
- <term>
- <mallctl>swap.fds</mallctl>
- (<type>int *</type>)
- <literal>r-</literal>
- [<option>--enable-swap</option>]
- </term>
- <listitem><para>When written to, the files associated with the
- specified file descriptors are contiguously mapped via
- <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry>. The resulting virtual memory
- region is preferred over anonymous
- <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> and
- <citerefentry><refentrytitle>sbrk</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> memory. Note that if a file's
- size is not a multiple of the page size, it is automatically truncated
- to the nearest page size multiple. See the
- <link linkend="swap.prezeroed"><mallctl>swap.prezeroed</mallctl></link>
- mallctl for specifying that the files are pre-zeroed.</para></listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1 id="debugging_malloc_problems">
- <title>DEBUGGING MALLOC PROBLEMS</title>
- <para>When debugging, it is a good idea to configure/build jemalloc with
- the <option>--enable-debug</option> and <option>--enable-fill</option>
- options, and recompile the program with suitable options and symbols for
- debugger support. When so configured, jemalloc incorporates a wide variety
- of run-time assertions that catch application errors such as double-free,
- write-after-free, etc.</para>
-
- <para>Programs often accidentally depend on &ldquo;uninitialized&rdquo;
- memory actually being filled with zero bytes. Junk filling
- (see the <link linkend="opt.junk"><mallctl>opt.junk</mallctl></link>
- option) tends to expose such bugs in the form of obviously incorrect
- results and/or coredumps. Conversely, zero
- filling (see the <link
- linkend="opt.zero"><mallctl>opt.zero</mallctl></link> option) eliminates
- the symptoms of such bugs. Between these two options, it is usually
- possible to quickly detect, diagnose, and eliminate such bugs.</para>
-
- <para>This implementation does not provide much detail about the problems
- it detects, because the performance impact for storing such information
- would be prohibitive. There are a number of allocator implementations
- available on the Internet which focus on detecting and pinpointing problems
- by trading performance for extra sanity checks and detailed
- diagnostics.</para>
- </refsect1>
- <refsect1 id="diagnostic_messages">
- <title>DIAGNOSTIC MESSAGES</title>
- <para>If any of the memory allocation/deallocation functions detect an
- error or warning condition, a message will be printed to file descriptor
- <constant>STDERR_FILENO</constant>. Errors will result in the process
- dumping core. If the <link
- linkend="opt.abort"><mallctl>opt.abort</mallctl></link> option is set, most
- warnings are treated as errors.</para>
-
- <para>The <varname>malloc_message</varname> variable allows the programmer
- to override the function which emits the text strings forming the errors
- and warnings if for some reason the <constant>STDERR_FILENO</constant> file
- descriptor is not suitable for this.
- <function>malloc_message<parameter/></function> takes the
- <parameter>cbopaque</parameter> pointer argument that is
- <constant>NULL</constant> unless overridden by the arguments in a call to
- <function>malloc_stats_print<parameter/></function>, followed by a string
- pointer. Please note that doing anything which tries to allocate memory in
- this function is likely to result in a crash or deadlock.</para>
-
- <para>All messages are prefixed by
- &ldquo;<computeroutput>&lt;jemalloc&gt;: </computeroutput>&rdquo;.</para>
- </refsect1>
- <refsect1 id="return_values">
- <title>RETURN VALUES</title>
- <refsect2>
- <title>Standard API</title>
- <para>The <function>malloc<parameter/></function> and
- <function>calloc<parameter/></function> functions return a pointer to the
- allocated memory if successful; otherwise a <constant>NULL</constant>
- pointer is returned and <varname>errno</varname> is set to
- <errorname>ENOMEM</errorname>.</para>
-
- <para>The <function>posix_memalign<parameter/></function> function
- returns the value 0 if successful; otherwise it returns an error value.
- The <function>posix_memalign<parameter/></function> function will fail
- if:
- <variablelist>
- <varlistentry>
- <term><errorname>EINVAL</errorname></term>
-
- <listitem><para>The <parameter>alignment</parameter> parameter is
- not a power of 2 at least as large as
- <code language="C">sizeof(<type>void *</type>)</code>.
- </para></listitem>
- </varlistentry>
- <varlistentry>
- <term><errorname>ENOMEM</errorname></term>
-
- <listitem><para>Memory allocation error.</para></listitem>
- </varlistentry>
- </variablelist>
- </para>
-
- <para>The <function>realloc<parameter/></function> function returns a
- pointer, possibly identical to <parameter>ptr</parameter>, to the
- allocated memory if successful; otherwise a <constant>NULL</constant>
- pointer is returned, and <varname>errno</varname> is set to
- <errorname>ENOMEM</errorname> if the error was the result of an
- allocation failure. The <function>realloc<parameter/></function>
- function always leaves the original buffer intact when an error occurs.
- </para>
-
- <para>The <function>free<parameter/></function> function returns no
- value.</para>
- </refsect2>
- <refsect2>
- <title>Non-standard API</title>
- <para>The <function>malloc_usable_size<parameter/></function> function
- returns the usable size of the allocation pointed to by
- <parameter>ptr</parameter>. </para>
-
- <para>The <function>mallctl<parameter/></function>,
- <function>mallctlnametomib<parameter/></function>, and
- <function>mallctlbymib<parameter/></function> functions return 0 on
- success; otherwise they return an error value. The functions will fail
- if:
- <variablelist>
- <varlistentry>
- <term><errorname>EINVAL</errorname></term>
-
- <listitem><para><parameter>newp</parameter> is not
- <constant>NULL</constant>, and <parameter>newlen</parameter> is too
- large or too small. Alternatively, <parameter>*oldlenp</parameter>
- is too large or too small; in this case as much data as possible
- are read despite the error.</para></listitem>
- </varlistentry>
- <varlistentry>
- <term><errorname>ENOMEM</errorname></term>
-
- <listitem><para><parameter>*oldlenp</parameter> is too short to
- hold the requested value.</para></listitem>
- </varlistentry>
- <varlistentry>
- <term><errorname>ENOENT</errorname></term>
-
- <listitem><para><parameter>name</parameter> or
- <parameter>mib</parameter> specifies an unknown/invalid
- value.</para></listitem>
- </varlistentry>
- <varlistentry>
- <term><errorname>EPERM</errorname></term>
-
- <listitem><para>Attempt to read or write void value, or attempt to
- write read-only value.</para></listitem>
- </varlistentry>
- <varlistentry>
- <term><errorname>EAGAIN</errorname></term>
-
- <listitem><para>A memory allocation failure
- occurred.</para></listitem>
- </varlistentry>
- <varlistentry>
- <term><errorname>EFAULT</errorname></term>
-
- <listitem><para>An interface with side effects failed in some way
- not directly related to <function>mallctl*<parameter/></function>
- read/write processing.</para></listitem>
- </varlistentry>
- </variablelist>
- </para>
- </refsect2>
- <refsect2>
- <title>Experimental API</title>
- <para>The <function>allocm<parameter/></function>,
- <function>rallocm<parameter/></function>,
- <function>sallocm<parameter/></function>, and
- <function>dallocm<parameter/></function> functions return
- <constant>ALLOCM_SUCCESS</constant> on success; otherwise they return an
- error value. The <function>allocm<parameter/></function> and
- <function>rallocm<parameter/></function> functions will fail if:
- <variablelist>
- <varlistentry>
- <term><errorname>ALLOCM_ERR_OOM</errorname></term>
-
- <listitem><para>Out of memory. Insufficient contiguous memory was
- available to service the allocation request. The
- <function>allocm<parameter/></function> function additionally sets
- <parameter>*ptr</parameter> to <constant>NULL</constant>, whereas
- the <function>rallocm<parameter/></function> function leaves
- <constant>*ptr</constant> unmodified.</para></listitem>
- </varlistentry>
- </variablelist>
- The <function>rallocm<parameter/></function> function will also
- fail if:
- <variablelist>
- <varlistentry>
- <term><errorname>ALLOCM_ERR_NOT_MOVED</errorname></term>
-
- <listitem><para><constant>ALLOCM_NO_MOVE</constant> was specified,
- but the reallocation request could not be serviced without moving
- the object.</para></listitem>
- </varlistentry>
- </variablelist>
- </para>
- </refsect2>
- </refsect1>
- <refsect1 id="environment">
- <title>ENVIRONMENT</title>
- <para>The following environment variable affects the execution of the
- allocation functions:
- <variablelist>
- <varlistentry>
- <term><envar>MALLOC_CONF</envar></term>
-
- <listitem><para>If the environment variable
- <envar>MALLOC_CONF</envar> is set, the characters it contains
- will be interpreted as options.</para></listitem>
- </varlistentry>
- </variablelist>
- </para>
- </refsect1>
- <refsect1 id="examples">
- <title>EXAMPLES</title>
- <para>To dump core whenever a problem occurs:
- <screen>ln -s 'abort:true' /etc/malloc.conf</screen>
- </para>
- <para>To specify in the source a chunk size that is 16 MiB:
- <programlisting language="C"><![CDATA[
-malloc_conf = "lg_chunk:24";]]></programlisting></para>
- </refsect1>
- <refsect1 id="see_also">
- <title>SEE ALSO</title>
- <para><citerefentry><refentrytitle>madvise</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sbrk</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>alloca</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>atexit</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>getpagesize</refentrytitle>
- <manvolnum>3</manvolnum></citerefentry></para>
- </refsect1>
- <refsect1 id="standards">
- <title>STANDARDS</title>
- <para>The <function>malloc<parameter/></function>,
- <function>calloc<parameter/></function>,
- <function>realloc<parameter/></function>, and
- <function>free<parameter/></function> functions conform to ISO/IEC
- 9899:1990 (&ldquo;ISO C90&rdquo;).</para>
-
- <para>The <function>posix_memalign<parameter/></function> function conforms
- to IEEE Std 1003.1-2001 (&ldquo;POSIX.1&rdquo;).</para>
- </refsect1>
-</refentry>
diff --git a/jemalloc/doc/manpages.xsl.in b/jemalloc/doc/manpages.xsl.in
deleted file mode 100644
index 88b2626..0000000
--- a/jemalloc/doc/manpages.xsl.in
+++ /dev/null
@@ -1,4 +0,0 @@
-<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
- <xsl:import href="@XSLROOT@/manpages/docbook.xsl"/>
- <xsl:import href="@abs_srcroot@doc/stylesheet.xsl"/>
-</xsl:stylesheet>
diff --git a/jemalloc/doc/stylesheet.xsl b/jemalloc/doc/stylesheet.xsl
deleted file mode 100644
index 4e334a8..0000000
--- a/jemalloc/doc/stylesheet.xsl
+++ /dev/null
@@ -1,7 +0,0 @@
-<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
- <xsl:param name="funcsynopsis.style">ansi</xsl:param>
- <xsl:param name="function.parens" select="1"/>
- <xsl:template match="mallctl">
- "<xsl:call-template name="inline.monoseq"/>"
- </xsl:template>
-</xsl:stylesheet>