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.\" __COPYRIGHT__
.\"
.\" Permission is hereby granted, free of charge, to any person obtaining
.\" a copy of this software and associated documentation files (the
.\" "Software"), to deal in the Software without restriction, including
.\" without limitation the rights to use, copy, modify, merge, publish,
.\" distribute, sublicense, and/or sell copies of the Software, and to
.\" permit persons to whom the Software is furnished to do so, subject to
.\" the following conditions:
.\"
.\" The above copyright notice and this permission notice shall be included
.\" in all copies or substantial portions of the Software.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
.\" KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
.\" WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
.\" NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
.\" LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
.\" OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
.\" WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
.\"
.\" doc/man/scons-time.1 0.96.C629 2006/11/18 11:50:43 knight
.\"
.\" ES - Example Start - indents and turns off line fill
.de ES
.RS
.nf
..
.\" EE - Example End - ends indent and turns line fill back on
.de EE
.RE
.fi
..
'\"==========================================================================
.de SF
.B scons-time func
[\fB-h\fR]
[\fB--chdir=\fIDIR\fR]
[\fB-f \fIFILE\fR]
[\fB--fmt=\fIFORMAT\fR]
[\fB--func=\fINAME\fR]
[\fB-p \fISTRING\fR]
[\fB-t \fINUMBER\fR]
[\fB--title= TITLE\fR]
[\fIARGUMENTS\fR]
..
'\"--------------------------------------------------------------------------
.de SY
.B scons-time mem
[\fB-h\fR]
[\fB--chdir=\fIDIR\fR]
[\fB-f \fIFILE\fR]
[\fB--fmt=\fIFORMAT\fR]
[\fB-p \fISTRING\fR]
[\fB--stage=\fISTAGE\fR]
[\fB-t \fINUMBER\fR]
[\fB--title=\fITITLE\fR]
[\fIARGUMENTS\fR]
..
'\"--------------------------------------------------------------------------
.de SO
.B scons-time obj
[\fB-h\fR]
[\fB--chdir=\fIDIR\fR]
[\fB-f \fIFILE\fR]
[\fB--fmt=\fIFORMAT\fR]
[\fB-p \fISTRING\fR]
[\fB--stage=\fISTAGE\fR]
[\fB-t \fINUMBER\fR]
[\fB--title=\fITITLE\fR]
[\fIARGUMENTS\fR]
..
'\"--------------------------------------------------------------------------
.de SR
.B scons-time run
[\fB-hnqv\fR]
[\fB--aegis=\fIPROJECT\fR]
[\fB-f \fIFILE\fR]
[\fB--number=\fINUMBER\fR]
[\fB--outdir=\fIOUTDIR\fR]
[\fB-p \fISTRING\fR]
[\fB--python=\fIPYTHON\fR]
[\fB-s \fIDIR\fR]
[\fB--scons=\fISCONS\fR]
[\fB--svn=\fIURL\fR]
[\fIARGUMENTS\fR]
..
'\"--------------------------------------------------------------------------
.de ST
.B scons-time time
[\fB-h\fR]
[\fB--chdir=\fIDIR\fR]
[\fB-f \fIFILE\fR]
[\fB--fmt=\fIFORMAT\fR]
[\fB-p \fISTRING\fR]
[\fB-t \fINUMBER\fR]
[\fB--title=\fITITLE\fR]
[\fB--which=\fIWHICH\fR]
[\fIARGUMENTS\fR]
..
.TH SCONS-TIME 1 "November 2006"
.SH NAME
scons-time \- generate and display SCons timing information
'\"==========================================================================
.SH SYNOPSIS
.B scons-time
.IR subcommand
[
.IR options ...
]
[
.IR arguments ...
]
'\"--------------------------------------------------------------------------
.SS "Generating Timing Information"
.SR
'\"--------------------------------------------------------------------------
.SS "Extracting Function Timings"
.SF
'\"--------------------------------------------------------------------------
.SS "Extracting Memory Statistics"
.SY
'\"--------------------------------------------------------------------------
.SS "Extracting Object Counts"
.SO
'\"--------------------------------------------------------------------------
.SS "Extracting Execution Times"
.ST
'\"--------------------------------------------------------------------------
.SS "Help Text"
.B scons-time help
.I SUBCOMMAND
[...]
'\"==========================================================================
.SH DESCRIPTION
The 
.B scons-time
command runs an SCons configuration
through a standard set of profiled timings
and can extract and graph information from the
resulting profiles and log files of those timings.
The action to be performed by the
.B scons-time
script is specified
by a subcommand, the first argument on the command line.
See the
.B SUBCOMMANDS
section below for information about the operation
of specific subcommands.
.P
The basic way to use
.B scons-time
is to run the
.B scons-time run
subcommand
(possibly multiple times)
to generate profile and log file output,
and then use one of the other
subcommands to display the results
captured in the profiles and log files
for a particular kind of information:
function timings
(the
.B scons-time func
subcommand),
total memory used
(the
.B scons-time mem
subcommand),
object counts
(the
.B scons-time obj
subcommand)
and overall execution time
(the
.B scons-time time
subcommand).
Options exist to place and find the
profiles and log files in separate directories,
to generate the output in a format suitable
for graphing with the
.BR gnuplot (1)
program,
and so on.
.P
There are two basic ways the
.B scons-time run
subcommand
is intended to be used
to gather timing statistics
for a configuration.
One is to use the
.B --svn=
option to test a configuration against
a list of revisions from the SCons Subversion repository.
This will generate a profile and timing log file
for every revision listed with the
.B --number=
option,
and can be used to look at the
impact of commited changes to the
SCons code base on a particular
configuration over time.
.P
The other way is to profile incremental changes to a
local SCons code base during a development cycle--that is,
to look at the performance impact of changes
you're making in the local tree.
In this mode,
you run the
.B scons-time run
subcommand
.I without
the
.B --svn=
option,
in which case it simply looks in the profile/log file output directory
(the current directory by default)
and automatically figures out the
.I next
run number for the output profile and log file.
Used in this way,
the development cycle goes something like:
make a change to SCons;
run
.B scons-time run
to profile it against a specific configuration;
make another change to SCons;
run
.B scons-time run
again to profile it;
etc.
'\"==========================================================================
.SH OPTIONS
The
.B scons-time
command only supports a few global options:
.TP
-h, --help
Displays the global help text and exits,
identical to the
.B scons-time help
subcommand.
.TP
-V, --version
Displays the
.B scons-time
version and exits.
.P
Most functionality is controlled by options
to the individual subcommands.
See the next section for information
about individual subcommand options.
'\"==========================================================================
.SH SUBCOMMANDS
The
.B scons-time
command supports the following
individual subcommands.
'\"--------------------------------------------------------------------------
.SS "The func Subcommand"
.SF
.P
The
.B scons-time func
subcommand displays timing information
for a specific Python function within SCons.
By default, it extracts information about the
.BR _main ()
function,
which includes the Python profiler timing
for all of SCons.
.P
The
.B scons-time func
subcommand extracts function timing information
from all the specified file arguments,
which should be Python profiler output files.
(Normally, these would be
.B *.prof
files generated by the
.B scons-time run
subcommand,
but they can actually be generated
by any Python profiler invocation.)
All file name arguments will be
globbed for on-disk files.
.P
If no arguments are specified,
then function timing information
will be extracted from all
.B *.prof
files,
or the subset of them
with a prefix specified by the
.B -p
option.
.P
Options include:
.TP
-C DIRECTORY, --chdir=DIRECTORY
Changes to the specified
.I DIRECTORY
before looking for the specified files
(or files that match the specified patterns).
.TP
-f FILE, --file=FILE
Reads configuration information from the specified
.IR FILE .
.TP
-fmt=FORMAT, --format=FORMAT
Reports the output in the specified
.IR FORMAT .
The formats currently supported are
.B ascii
(the default)
and
.BR gnuplot .
.TP
--func=NAME
Extracts timings for the specified function
.IR NAME .
The default is to report cumulative timings for the
.BR _main ()
function,
which contains the entire SCons run.
.TP
-h, --help
Displays help text for the
.B scons-time func
subcommand.
.TP
-p STRING, --prefix=STRING
Specifies the prefix string for profiles
from which to extract function timing information.
This will be used to search for profiles
if no arguments are specified on the command line.
.TP
-t NUMBER, --tail=NUMBER
Only extracts function timings from the last
.I NUMBER
files.
'\"--------------------------------------------------------------------------
.SS "The help Subcommand"
.B scons-time help
.I SUBCOMMAND
[...]
The
.B help
subcommand prints help text for any
other subcommands listed as later arguments on the command line.
'\"--------------------------------------------------------------------------
.SS "The mem Subcommand"
.SY
.P
The
.B scons-time mem
subcommand displays how much memory SCons uses.
.P
The
.B scons-time mem
subcommand extracts memory use information
from all the specified file arguments,
which should be files containing output from
running SCons with the
.B --debug=memory
option.
(Normally, these would be
.B *.log
files generated by the
.B scons-time run
subcommand.)
All file name arguments will be
globbed for on-disk files.
.P
If no arguments are specified,
then memory information
will be extracted from all
.B *.log
files,
or the subset of them
with a prefix specified by the
.B -p
option.
.P
.TP
-C DIR, --chdir=DIR
Changes to the specified
.I DIRECTORY
before looking for the specified files
(or files that match the specified patterns).
.TP
-f FILE, --file=FILE
Reads configuration information from the specified
.IR FILE .
.TP
-fmt=FORMAT, --format=FORMAT
Reports the output in the specified
.IR FORMAT .
The formats currently supported are
.B ascii
(the default)
and
.BR gnuplot .
.TP
-h, --help
Displays help text for the
.B scons-time mem
subcommand.
.TP
-p STRING, --prefix=STRING
Specifies the prefix string for log files
from which to extract memory usage information.
This will be used to search for log files
if no arguments are specified on the command line.
.TP
--stage=STAGE
Prints the memory used at the end of the specified
.IR STAGE :
.B pre-read
(before the SConscript files are read),
.B post-read ,
(after the SConscript files are read),
.B pre-build
(before any targets are built)
or
.B post-build
(after any targets are built).
If no
.B --stage
option is specified,
the default behavior is
.BR post-build ,
which reports the final amount of memory
used by SCons during each run.
.TP
-t NUMBER, --tail=NUMBER
Only reports memory statistics from the last
.I NUMBER
files.
'\"--------------------------------------------------------------------------
.SS "The obj Subcommand"
.SO
.P
The
.B scons-time obj
subcommand displays how many objects of a specific named type
are created by SCons.
.P
The
.B scons-time obj
subcommand extracts object counts
from all the specified file arguments,
which should be files containing output from
running SCons with the
.B --debug=count
option.
(Normally, these would be
.B *.log
files generated by the
.B scons-time run
subcommand.)
All file name arguments will be
globbed for on-disk files.
.P
If no arguments are specified,
then object counts
will be extracted from all
.B *.log
files,
or the subset of them
with a prefix specified by the
.B -p
option.
.TP
-C DIR, --chdir=DIR
Changes to the specified
.I DIRECTORY
before looking for the specified files
(or files that match the specified patterns).
.TP
-f FILE, --file=FILE
Reads configuration information from the specified
.IR FILE .
.TP
-fmt=FORMAT, --format=FORMAT
Reports the output in the specified
.IR FORMAT .
The formats currently supported are
.B ascii
(the default)
and
.BR gnuplot .
.TP
-h, --help
Displays help text for the
.B scons-time obj
subcommand.
.TP
-p STRING, --prefix=STRING
Specifies the prefix string for log files
from which to extract object counts.
This will be used to search for log files
if no arguments are specified on the command line.
.TP
--stage=STAGE
Prints the object count at the end of the specified
.IR STAGE :
.B pre-read
(before the SConscript files are read),
.B post-read ,
(after the SConscript files are read),
.B pre-build
(before any targets are built)
or
.B post-build
(after any targets are built).
If no
.B --stage
option is specified,
the default behavior is
.BR post-build ,
which reports the final object count during each run.
.TP
-t NUMBER, --tail=NUMBER
Only reports object counts from the last
.I NUMBER
files.
'\"--------------------------------------------------------------------------
.SS "The run Subcommand"
.SR
The
.B scons-time run
subcommand is the basic subcommand
for profiling a specific configuration
against a version of SCons.
.P
The configuration to be tested
is specified as a list of files
or directories that will be unpacked or copied
into a temporary directory
in which SCons will be invoked.
The
.B scons-time run
subcommand understands file suffixes like
.BR .tar ,
.BR .tar.gz ,
.BR .tgz
and
.BR .zip
and will unpack their contents into a temporary directory.
If more than one argument is specified,
each one will be unpacked or copied
into the temporary directory "on top of"
the previous archives or directories,
so the expectation is that multiple
specified archives share the same directory layout.
.P
Once the file or directory arguments are unpacked or
copied to the temporary directory,
the
.B scons-time run
subcommand runs the
requested version of SCons
against the configuration
three times:
.TP
Startup
SCons is run with the
.B --help
option so that just the SConscript files are read,
and then the default help text is printed.
This profiles just the perceived "overhead" of starting up SCons
and processing the SConscript files.
.TP
Full build
SCons is run to build everything specified in the configuration.
Specific targets to be passed in on the command l ine
may be specified by the
.B targets
keyword in a configuration file; see below for details.
.TP
Rebuild
SCons is run again on the same just-built directory.
If the dependencies in the SCons configuration are correct,
this should be an up-to-date, "do nothing" rebuild.
.P
Each invocation captures the output log file and a profile.
.P
The
.B scons-time run
subcommand supports the following options:
.TP
--aegis=PROJECT
Specifies the Aegis
.I PROJECT
from which the
version(s) of
.B scons
being timed will be extracted.
When
.B --aegis
is specified, the
.BI --number= NUMBER
option specifies delta numbers
that will be tested.
Output from each invocation run will be placed in file
names that match the Aegis delta numbers.
If the
.B --number=
option is not specified,
then the default behavior is to time the
tip of the specified
.IR PROJECT .
.TP
-f FILE, --file=FILE
Reads configuration information from the specified
.IR FILE .
This often provides a more convenient way to specify and
collect parameters associated with a specific timing configuration
than specifying them on the command line.
See the
.B CONFIGURATION FILE
section below
for information about the configuration file parameters.
.TP
-h, --help
Displays help text for the
.B scons-time run
subcommand.
.TP
-n, --no-exec
Do not execute commands,
just printing the command-line equivalents of what would be executed.
Note that the
.B scons-time
script actually executes its actions in Python,
where possible,
for portability.
The commands displayed are UNIX
.I equivalents
of what it's doing.
.TP
--number=NUMBER
Specifies the run number to be used in the names of
the log files and profile outputs generated by this run.
.IP
When used in conjuction with the
.BI --aegis= PROJECT
option,
.I NUMBER
specifies one or more comma-separated Aegis delta numbers
that will be retrieved automatically from the specified Aegis
.IR PROJECT .
.IP
When used in conjuction with the
.BI --svn= URL
option,
.I NUMBER
specifies one or more comma-separated Subversion revision numbers
that will be retrieved automatically from the Subversion
repository at the specified
.IR URL .
Ranges of delta or revision numbers
may be specified be separating two numbers
with a hyphen
.RB ( \- ).
.P
Example:
.ES
% scons-time run --svn=http://scons.tigris.org/svn/trunk --num=1247,1249-1252 .
.EE
.TP
-p STRING, --prefix=STRING
Specifies the prefix string to be used for all of the log files
and profiles generated by this run.
The default is derived from the first
specified argument:
if the first argument is a directory,
the default prefix is the name of the directory;
if the first argument is an archive
(tar or zip file),
the default prefix is the the base name of the archive,
that is, what remains after stripping the archive suffix
.RB ( .tgz ", " .tar.gz " or " .zip ).
.TP
--python=PYTHON
Specifies a path to the Python executable to be used
for the timing runs.
The default is to use the same Python executable that
is running the
.B scons-time
command itself.
.TP
-q, --quiet
Suppresses display of the command lines being executed.
.TP
-s DIR, --subdir=DIR
Specifies the name of directory or subdirectory
from which the commands should be executed.
The default is XXX
.TP
--scons=SCONS
Specifies a path to the SCons script to be used
for the timing runs.
The default is XXX
.TP
--svn=URL, --subversion=URL
Specifies the
.I URL
of the Subversion repository from which the
version(s) of
.B scons
being timed will be extracted.
When
.B --svn
is specified, the
.BI --number= NUMBER
option specifies revision numbers
that will be tested.
Output from each invocation run will be placed in file
names that match the Subversion revision numbers.
If the
.B --number=
option is not specified,
then the default behavior is to time the
.B HEAD
of the specified
.IR URL .
.TP
-v, --verbose
Displays the output from individual commands to the screen
(in addition to capturing the output in log files).
'\"--------------------------------------------------------------------------
.SS "The time Subcommand"
.ST
.P
The
.B scons-time time
subcommand displays SCons execution times
as reported by the
.B scons --debug=time
option.
.P
The
.B scons-time time
subcommand extracts SCons timing
from all the specified file arguments,
which should be files containing output from
running SCons with the
.B --debug=time
option.
(Normally, these would be
.B *.log
files generated by the
.B scons-time run
subcommand.)
All file name arguments will be
globbed for on-disk files.
.P
If no arguments are specified,
then execution timings
will be extracted from all
.B *.log
files,
or the subset of them
with a prefix specified by the
.B -p
option.
.TP
-C DIR, --chdir=DIR
Changes to the specified
.I DIRECTORY
before looking for the specified files
(or files that match the specified patterns).
.TP
-f FILE, --file=FILE
Reads configuration information from the specified
.IR FILE .
.TP
-fmt=FORMAT, --format=FORMAT
Reports the output in the specified
.IR FORMAT .
The formats currently supported are
.B ascii
(the default)
and
.BR gnuplot .
.TP
-h, --help
Displays help text for the
.B scons-time time
subcommand.
.TP
-p STRING, --prefix=STRING
Specifies the prefix string for log files
from which to extract execution timings.
This will be used to search for log files
if no arguments are specified on the command line.
.TP
-t NUMBER, --tail=NUMBER
Only reports object counts from the last
.I NUMBER
files.
.TP
--which=WHICH
Prints the execution time for the specified
.IR WHICH
value:
.B total
(the total execution time),
.B SConscripts
(total execution time for the SConscript files themselves),
.B SCons
(exectuion time in SCons code itself)
or
.B commands
(execution time of the commands and other actions
used to build targets).
If no
.B --which
option is specified,
the default behavior is
.BR total ,
which reports the total execution time for each run.
'\"==========================================================================
.SH CONFIGURATION FILE
Various
.B scons-time
subcommands can read information from a specified
configuration file when passed the
.B \-f
or
.B \--file
options.
The configuration file is actually executed as a Python script.
Setting Python variables in the configuration file
controls the behavior of the
.B scons-time
script more conveniently than having to specify
command-line options or arguments for every run,
and provides a handy way to "shrink-wrap"
the necessary information for producing (and reporting)
consistent timing runs for a given configuration.
.TP
.B aegis
The Aegis executable for extracting deltas.
The default is simply
.BR aegis .
.TP
.B aegis_project
The Aegis project from which deltas should be extracted.
The default is whatever is specified
with the
.B --aegis=
command-line option.
.TP
.B initial_commands
A list of commands that will be executed
before the actual timed
.B scons
runs.
This can be used for commands that are necessary
to prepare the source tree\-for example,
creating a configuration file
that should not be part of the timed run.
.TP
.B key_location
The location of the key on Gnuplot graphing information
generated with the
.BR --format=gnuplot
option.
The default is
.BR "bottom left" .
.TP
.B prefix
The file name prefix to be used when
running or extracting timing for this configuration.
.TP
.B python
The path name of the Python executable
to be used when running or extracting information
for this configuration.
The default is the same version of Python
used to run the SCons
.TP
.B scons
The path name of the SCons script to be used
when running or extracting information
for this configuration.
The default is simply
.BR scons .
.TP
.B scons_flags
The
.B scons
flags used when running SCons to collect timing information.
The default value is
.BR "--debug=count --debug=memory --debug=time --debug=memoizer" .
.TP
.B scons_lib_dir
.TP
.B scons_wrapper
.TP
.B startup_targets
.TP
.B subdir
The subdirectory of the project into which the
.B scons-time
script should change
before executing the SCons commands to time.
.TP
.B subversion_url
The Subversion URL from
.TP
.B svn
The subversion executable used to
check out revisions of SCons to be timed.
The default is simple
.BR svn .
.TP
.B svn_co_flag
.TP
.B tar
.TP
.B targets
A string containing the targets that should be added to
the command line of every timed
.B scons
run.
This can be used to restrict what's being timed to a
subset of the full build for the configuration.
.TP
.B targets0
.TP
.B targets1
.TP
.B targets2
.TP
.B title
.TP
.B unzip
.TP
.B verbose
.TP
.B vertical_bars
'\"--------------------------------------------------------------------------
.SS Example
Here is an example
.B scons-time
configuration file
for a hypothetical sample project:
.P
.ES
# The project doesn't use SCons natively (yet), so we're
# timing a separate set of SConscript files that we lay
# on top of the vanilla unpacked project tarball.
arguments = ['project-1.2.tgz', 'project-SConscripts.tar']

# The subdirectory name contains the project version number,
# so tell scons-time to chdir there before building.
subdir = 'project-1.2'

# Set the prefix so output log files and profiles are named:
#     project-000-[012].{log,prof}
#     project-001-[012].{log,prof}
# etc.
prefix = 'project'

# The SConscript files being tested don't do any SConf
# configuration, so run their normal ./configure script
# before we invoke SCons.
initial_commands = [
    './configure',
]

# Only time building the bin/project executable.
targets = 'bin/project'

# Time against SCons revisions of the branches/core branch
subversion_url = 'http://scons.tigris.org/svn/scons/branches/core'
.EE
'\"==========================================================================
.SH ENVIRONMENT
The
.B
scons-time
script uses the following environment variables:
.TP
.B PRESERVE
If this value is set,
the
.B scons-time
script will
.I not
remove the temporary directory or directories
in which it builds the specified configuration
or downloads a specific version of SCons.
'\"==========================================================================
.SH "SEE ALSO"
.BR gnuplot (1),
.BR scons (1)

.SH AUTHORS
Steven Knight <knight at baldmt dot com>