[svn-r18426] Description:

	Rename "old" cache code and routines from H5AC to H5AC1.

Tested on:
	Mac OS X/32 10.6.2 (amazon) w/debug, prod & parallel
	(h5committest not required on this branch)

1 files changed, 1081 insertions, 0 deletions

diff --git a/src/H5C1private.h b/src/H5C1private.h
new file mode 100644
index 0000000..d508346
--- /dev/null
+++ b/src/H5C1private.h
@@ -0,0 +1,1081 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:		H5C1private.h
+ *			6/3/04
+ *			John Mainzer
+ *
+ * Purpose:		Constants and typedefs available to the rest of the
+ *			library.
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef _H5C1private_H
+#define _H5C1private_H
+
+#include "H5C1public.h"		/*public prototypes			     */
+
+/* Pivate headers needed by this header */
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5Fprivate.h"		/* File access				*/
+
+
+#define H5C1_DO_SANITY_CHECKS		0
+#define H5C1_DO_EXTREME_SANITY_CHECKS	0
+
+/* This sanity checking constant was picked out of the air.  Increase
+ * or decrease it if appropriate.  Its purposes is to detect corrupt
+ * object sizes, so it probably doesn't matter if it is a bit big.
+ *
+ *					JRM - 5/17/04
+ */
+#define H5C1_MAX_ENTRY_SIZE		((size_t)(10 * 1024 * 1024))
+
+/* H5C1_COLLECT_CACHE_STATS controls overall collection of statistics
+ * on cache activity.  In general, this #define should be set to 0.
+ */
+#define H5C1_COLLECT_CACHE_STATS	0
+
+/* H5C1_COLLECT_CACHE_ENTRY_STATS controls collection of statistics
+ * in individual cache entries.
+ *
+ * H5C1_COLLECT_CACHE_ENTRY_STATS should only be defined to true if
+ * H5C1_COLLECT_CACHE_STATS is also defined to true.
+ */
+#if H5C1_COLLECT_CACHE_STATS
+
+#define H5C1_COLLECT_CACHE_ENTRY_STATS	1
+
+#else
+
+#define H5C1_COLLECT_CACHE_ENTRY_STATS	0
+
+#endif /* H5C1_COLLECT_CACHE_STATS */
+
+
+#ifdef H5_HAVE_PARALLEL
+
+/* we must maintain the clean and dirty LRU lists when we are compiled
+ * with parallel support.
+ */
+#define H5C1_MAINTAIN_CLEAN_AND_DIRTY_LRU_LISTS  1
+
+#else /* H5_HAVE_PARALLEL */
+
+/* The clean and dirty LRU lists don't buy us anything here -- we may
+ * want them on for testing on occasion, but in general they should be
+ * off.
+ */
+#define H5C1_MAINTAIN_CLEAN_AND_DIRTY_LRU_LISTS  0
+
+#endif /* H5_HAVE_PARALLEL */
+
+
+/* Typedef for the main structure for the cache (defined in H5Cpkg.h) */
+
+typedef struct H5C1_t H5C1_t;
+
+
+/*
+ * Class methods pertaining to caching.	 Each type of cached object will
+ * have a constant variable with permanent life-span that describes how
+ * to cache the object.	 That variable will be of type H5C1_class_t and
+ * have the following required fields...
+ *
+ * LOAD:	Loads an object from disk to memory.  The function
+ *		should allocate some data structure and return it.
+ *
+ * FLUSH:	Writes some data structure back to disk.  It would be
+ *		wise for the data structure to include dirty flags to
+ *		indicate whether it really needs to be written.	 This
+ *		function is also responsible for freeing memory allocated
+ *		by the LOAD method if the DEST argument is non-zero (by
+ *              calling the DEST method).
+ *
+ * DEST:	Just frees memory allocated by the LOAD method.
+ *
+ * CLEAR:	Just marks object as non-dirty.
+ *
+ * SIZE:	Report the size (on disk) of the specified cache object.
+ *		Note that the space allocated on disk may not be contiguous.
+ */
+
+#define H5C1_CALLBACK__NO_FLAGS_SET		0x0
+#define H5C1_CALLBACK__SIZE_CHANGED_FLAG		0x1
+#define H5C1_CALLBACK__RENAMED_FLAG		0x2
+
+typedef void *(*H5C1_load_func_t)(H5F_t *f,
+                                 hid_t dxpl_id,
+                                 haddr_t addr,
+                                 const void *udata1,
+                                 void *udata2);
+typedef herr_t (*H5C1_flush_func_t)(H5F_t *f,
+                                   hid_t dxpl_id,
+                                   hbool_t dest,
+                                   haddr_t addr,
+                                   void *thing,
+				   unsigned * flags_ptr);
+typedef herr_t (*H5C1_dest_func_t)(H5F_t *f,
+                                  void *thing);
+typedef herr_t (*H5C1_clear_func_t)(H5F_t *f,
+                                   void *thing,
+                                   hbool_t dest);
+typedef herr_t (*H5C1_size_func_t)(const H5F_t *f,
+                                  const void *thing,
+                                  size_t *size_ptr);
+
+typedef struct H5C1_class_t {
+    int			id;
+    H5C1_load_func_t	load;
+    H5C1_flush_func_t	flush;
+    H5C1_dest_func_t	dest;
+    H5C1_clear_func_t	clear;
+    H5C1_size_func_t	size;
+} H5C1_class_t;
+
+
+/* Type defintions of call back functions used by the cache as a whole */
+
+typedef herr_t (*H5C1_write_permitted_func_t)(const H5F_t *f,
+                                             hid_t dxpl_id,
+                                             hbool_t * write_permitted_ptr);
+
+typedef herr_t (*H5C1_log_flush_func_t)(H5C1_t * cache_ptr,
+                                       haddr_t addr,
+                                       hbool_t was_dirty,
+                                       unsigned flags,
+                                       int type_id);
+
+/* Upper and lower limits on cache size.  These limits are picked
+ * out of a hat -- you should be able to change them as necessary.
+ *
+ * However, if you need a very big cache, you should also increase the
+ * size of the hash table (H5C1__HASH_TABLE_LEN in H5Cpkg.h).  The current
+ * upper bound on cache size is rather large for the current hash table
+ * size.
+ */
+
+#define H5C1__MAX_MAX_CACHE_SIZE		((size_t)(128 * 1024 * 1024))
+#define H5C1__MIN_MAX_CACHE_SIZE		((size_t)(1024))
+
+
+/* Default max cache size and min clean size are give here to make
+ * them generally accessable.
+ */
+
+#define H5C1__DEFAULT_MAX_CACHE_SIZE     ((size_t)(4 * 1024 * 1024))
+#define H5C1__DEFAULT_MIN_CLEAN_SIZE     ((size_t)(2 * 1024 * 1024))
+
+
+/****************************************************************************
+ *
+ * structure H5C1_cache_entry_t
+ *
+ * Instances of the H5C1_cache_entry_t structure are used to store cache
+ * entries in a hash table and sometimes in a skip list.
+ * See H5SL.c for the particulars of the skip list.
+ *
+ * In typical application, this structure is the first field in a
+ * structure to be cached.  For historical reasons, the external module
+ * is responsible for managing the is_dirty field (this is no longer
+ * completely true.  See the comment on the is_dirty field for details).
+ * All other fields are managed by the cache.
+ *
+ * The fields of this structure are discussed individually below:
+ *
+ *						JRM - 4/26/04
+ *
+ * magic:       Unsigned 32 bit integer that must always be set to
+ *              H5C1__H5C1_CACHE_ENTRY_T_MAGIC when the entry is valid.
+ *              The field must be set to H5C1__H5C1_CACHE_ENTRY_T_BAD_MAGIC
+ *              just before the entry is freed.
+ *
+ *              This is necessary, as the LRU list can be changed out
+ *              from under H5C1_make_space_in_cache() by the flush
+ *              callback which may change the size of an existing entry,
+ *              and/or load a new entry while serializing the target entry.
+ *
+ *              This in turn can cause a recursive call to
+ *              H5C1_make_space_in_cache() which may either flush or evict
+ *              the next entry that the first invocation of that function
+ *              was about to examine.
+ *
+ *              The magic field allows H5C1_make_space_in_cache() to
+ *              detect this case, and re-start its scan from the bottom
+ *              of the LRU when this situation occurs.
+ *
+ *              This field is only compiled in debug mode.
+ *
+ * addr:	Base address of the cache entry on disk.
+ *
+ * size:	Length of the cache entry on disk.  Note that unlike normal
+ *		caches, the entries in this cache are of variable length.
+ *		The entries should never overlap, and when we do writebacks,
+ *		we will want to writeback adjacent entries where possible.
+ *
+ *		NB: At present, entries need not be contiguous on disk.  Until
+ *		    we fix this, we can't do much with writing back adjacent
+ *		    entries.
+ *
+ * type:	Pointer to the instance of H5C1_class_t containing pointers
+ *		to the methods for cache entries of the current type.  This
+ *		field should be NULL when the instance of H5C1_cache_entry_t
+ *		is not in use.
+ *
+ *		The name is not particularly descriptive, but is retained
+ *		to avoid changes in existing code.
+ *
+ * is_dirty:	Boolean flag indicating whether the contents of the cache
+ *		entry has been modified since the last time it was written
+ *		to disk.
+ *
+ *		NOTE: For historical reasons, this field is not maintained
+ *		      by the cache.  Instead, the module using the cache
+ *		      sets this flag when it modifies the entry, and the
+ *		      flush and clear functions supplied by that module
+ *		      reset the dirty when appropriate.
+ *
+ *		      This is a bit quirky, so we may want to change this
+ *		      someday.  However it will require a change in the
+ *		      cache interface.
+ *
+ *		Update: Management of the is_dirty field has been largely
+ *		      moved into the cache.  The only remaining exceptions
+ *		      are the flush and clear functions supplied by the
+ *		      modules using the cache.  These still clear the
+ *		      is_dirty field as before.  -- JRM 7/5/05
+ *
+ * dirtied:	Boolean flag used to indicate that the entry has been
+ * 		dirtied while protected.
+ *
+ * 		This field is set to FALSE in the protect call, and may
+ * 		be set to TRUE by the
+ * 		H5C1_mark_pinned_or_protected_entry_dirty()
+ * 		call at an time prior to the unprotect call.
+ *
+ * 		The H5C1_mark_pinned_or_protected_entry_dirty() call exists
+ * 		as a convenience function for the fractal heap code which
+ * 		may not know if an entry is protected or pinned, but knows
+ * 		that is either protected or pinned.  The dirtied field was
+ * 		added as in the parallel case, it is necessary to know
+ * 		whether a protected entry was dirty prior to the protect call.
+ *
+ * is_protected: Boolean flag indicating whether this entry is protected
+ *		(or locked, to use more conventional terms).  When it is
+ *		protected, the entry cannot be flushed or accessed until
+ *		it is unprotected (or unlocked -- again to use more
+ *		conventional terms).
+ *
+ *		Note that protected entries are removed from the LRU lists
+ *		and inserted on the protected list.
+ *
+ * is_read_only: Boolean flag that is only meaningful if is_protected is
+ * 		TRUE.  In this circumstance, it indicates whether the
+ * 		entry has been protected read only, or read/write.
+ *
+ * 		If the entry has been protected read only (i.e. is_protected
+ * 		and is_read_only are both TRUE), we allow the entry to be
+ * 		protected more than once.
+ *
+ *		In this case, the number of readers is maintained in the
+ *		ro_ref_count field (see below), and unprotect calls simply
+ *		decrement that field until it drops to zero, at which point
+ *		the entry is actually unprotected.
+ *
+ * ro_ref_count: Integer field used to maintain a count of the number of
+ * 		outstanding read only protects on this entry.  This field
+ * 		must be zero whenever either is_protected or is_read_only
+ * 		are TRUE.
+ *
+ * is_pinned:	Boolean flag indicating whether the entry has been pinned
+ * 		in the cache.
+ *
+ * 		For very hot entries, the protect / unprotect overhead
+ * 		can become excessive.  Thus the cache has been extended
+ * 		to allow an entry to be "pinned" in the cache.
+ *
+ * 		Pinning an entry in the cache has several implications:
+ *
+ * 		1) A pinned entry cannot be evicted.  Thus unprotected
+ * 		   pinned entries must be stored in the pinned entry
+ * 		   list, instead of being managed by the replacement
+ * 		   policy code (LRU at present).
+ *
+ * 		2) A pinned entry can be accessed or modified at any time.
+ * 		   Therefore, the cache must check with the entry owner
+ * 		   before flushing it.  If permission is denied, the
+ * 		   cache does not flush the entry.
+ *
+ * 		3) A pinned entry can be marked as dirty (and possibly
+ *		   change size) while it is unprotected.
+ *
+ *		4) The flush-destroy code must allow pinned entries to
+ *		   be unpinned (and possibly unprotected) during the
+ *		   flush.
+ *
+ *		   					JRM -- 3/16/06
+ *
+ * in_slist:	Boolean flag indicating whether the entry is in the skip list
+ *		As a general rule, entries are placed in the list when they
+ *              are marked dirty.  However they may remain in the list after
+ *              being flushed.
+ *
+ *              Update: Dirty entries are now removed from the skip list
+ *			when they are flushed.
+ *
+ * flush_marker:  Boolean flag indicating that the entry is to be flushed
+ *		the next time H5C1_flush_cache() is called with the
+ *		H5C1__FLUSH_MARKED_ENTRIES_FLAG.  The flag is reset when
+ *		the entry is flushed for whatever reason.
+ *
+ * clear_on_unprotect:  Boolean flag used only in PHDF5.  When H5C is used
+ *		to implement the metadata cache In the parallel case, only
+ *		the cache with mpi rank 0 is allowed to actually write to
+ *		file -- all other caches must retain dirty entries until they
+ *		are advised that the entry is clean.
+ *
+ *		This flag is used in the case that such an advisory is
+ *		received when the entry is protected.  If it is set when an
+ *		entry is unprotected, and the dirtied flag is not set in
+ *		the unprotect, the entry's is_dirty flag is reset by flushing
+ *		it with the H5C1__FLUSH_CLEAR_ONLY_FLAG.
+ *
+ * flush_in_progress:  Boolean flag that is set to true iff the entry
+ * 		is in the process of being flushed.  This allows the cache
+ * 		to detect when a call is the result of a flush callback.
+ *
+ * destroy_in_progress:  Boolean flag that is set to true iff the entry
+ * 		is in the process of being flushed and destroyed.
+ *
+ *
+ * Fields supporting the hash table:
+ *
+ * Fields in the cache are indexed by a more or less conventional hash table.
+ * If there are multiple entries in any hash bin, they are stored in a doubly
+ * linked list.
+ *
+ * ht_next:	Next pointer used by the hash table to store multiple
+ *		entries in a single hash bin.  This field points to the
+ *		next entry in the doubly linked list of entries in the
+ *		hash bin, or NULL if there is no next entry.
+ *
+ * ht_prev:     Prev pointer used by the hash table to store multiple
+ *              entries in a single hash bin.  This field points to the
+ *              previous entry in the doubly linked list of entries in
+ *		the hash bin, or NULL if there is no previuos entry.
+ *
+ *
+ * Fields supporting replacement policies:
+ *
+ * The cache must have a replacement policy, and it will usually be
+ * necessary for this structure to contain fields supporting that policy.
+ *
+ * While there has been interest in several replacement policies for
+ * this cache, the initial development schedule is tight.  Thus I have
+ * elected to support only a modified LRU policy for the first cut.
+ *
+ * When additional replacement policies are added, the fields in this
+ * section will be used in different ways or not at all.  Thus the
+ * documentation of these fields is repeated for each replacement policy.
+ *
+ * Modified LRU:
+ *
+ * When operating in parallel mode, we must ensure that a read does not
+ * cause a write.  If it does, the process will hang, as the write will
+ * be collective and the other processes will not know to participate.
+ *
+ * To deal with this issue, I have modified the usual LRU policy by adding
+ * clean and dirty LRU lists to the usual LRU list.  When reading in
+ * parallel mode, we evict from the clean LRU list only.  This implies
+ * that we must try to ensure that the clean LRU list is reasonably well
+ * stocked.  See the comments on H5C1_t in H5Cpkg.h for more details.
+ *
+ * Note that even if we start with a completely clean cache, a sequence
+ * of protects without unprotects can empty the clean LRU list.  In this
+ * case, the cache must grow temporarily.  At the next write, we will
+ * attempt to evict enough entries to get the cache down to its nominal
+ * maximum size.
+ *
+ * The use of the replacement policy fields under the Modified LRU policy
+ * is discussed below:
+ *
+ * next:	Next pointer in either the LRU or the protected list,
+ *		depending on the current value of protected.  If there
+ *		is no next entry on the list, this field should be set
+ *		to NULL.
+ *
+ * prev:	Prev pointer in either the LRU or the protected list,
+ *		depending on the current value of protected.  If there
+ *		is no previous entry on the list, this field should be
+ *		set to NULL.
+ *
+ * aux_next:	Next pointer on either the clean or dirty LRU lists.
+ *		This entry should be NULL when protected is true.  When
+ *		protected is false, and dirty is true, it should point
+ *		to the next item on the dirty LRU list.  When protected
+ *		is false, and dirty is false, it should point to the
+ *		next item on the clean LRU list.  In either case, when
+ *		there is no next item, it should be NULL.
+ *
+ * aux_prev:	Previous pointer on either the clean or dirty LRU lists.
+ *		This entry should be NULL when protected is true.  When
+ *		protected is false, and dirty is true, it should point
+ *		to the previous item on the dirty LRU list.  When protected
+ *		is false, and dirty is false, it should point to the
+ *		previous item on the clean LRU list.  In either case, when
+ *		there is no previous item, it should be NULL.
+ *
+ *
+ * Cache entry stats collection fields:
+ *
+ * These fields should only be compiled in when both H5C1_COLLECT_CACHE_STATS
+ * and H5C1_COLLECT_CACHE_ENTRY_STATS are true.  When present, they allow
+ * collection of statistics on individual cache entries.
+ *
+ * accesses:	int32_t containing the number of times this cache entry has
+ *		been referenced in its lifetime.
+ *
+ * clears:	int32_t containing the number of times this cache entry has
+ *              been cleared in its life time.
+ *
+ * flushes:	int32_t containing the number of times this cache entry has
+ *              been flushed to file in its life time.
+ *
+ * pins:	int32_t containing the number of times this cache entry has
+ * 		been pinned in cache in its life time.
+ *
+ ****************************************************************************/
+
+#ifndef NDEBUG
+#define H5C1__H5C1_CACHE_ENTRY_T_MAGIC          0x005CAC0A
+#define H5C1__H5C1_CACHE_ENTRY_T_BAD_MAGIC      0xDeadBeef
+#endif /* NDEBUG */
+
+typedef struct H5C1_cache_entry_t
+{
+#ifndef NDEBUG
+    uint32_t		magic;
+#endif /* NDEBUG */
+    haddr_t		addr;
+    size_t		size;
+    const H5C1_class_t *	type;
+    hbool_t		is_dirty;
+    hbool_t		dirtied;
+    hbool_t		is_protected;
+    hbool_t		is_read_only;
+    int			ro_ref_count;
+    hbool_t		is_pinned;
+    hbool_t		in_slist;
+    hbool_t		flush_marker;
+#ifdef H5_HAVE_PARALLEL
+    hbool_t		clear_on_unprotect;
+#endif /* H5_HAVE_PARALLEL */
+    hbool_t		flush_in_progress;
+    hbool_t		destroy_in_progress;
+
+    /* fields supporting the hash table: */
+
+    struct H5C1_cache_entry_t *	ht_next;
+    struct H5C1_cache_entry_t *	ht_prev;
+
+    /* fields supporting replacement policies: */
+
+    struct H5C1_cache_entry_t *	next;
+    struct H5C1_cache_entry_t *	prev;
+    struct H5C1_cache_entry_t *	aux_next;
+    struct H5C1_cache_entry_t *	aux_prev;
+
+#if H5C1_COLLECT_CACHE_ENTRY_STATS
+
+    /* cache entry stats fields */
+
+    int32_t			accesses;
+    int32_t			clears;
+    int32_t			flushes;
+    int32_t			pins;
+
+#endif /* H5C1_COLLECT_CACHE_ENTRY_STATS */
+
+} H5C1_cache_entry_t;
+
+
+/****************************************************************************
+ *
+ * structure H5C1_auto_size_ctl_t
+ *
+ * Instances of H5C1_auto_size_ctl_t are used to get and set the control
+ * fields for automatic cache re-sizing.
+ *
+ * The fields of the structure are discussed individually below:
+ *
+ * version: Integer field containing the version number of this version
+ *	of the H5C1_auto_size_ctl_t structure.  Any instance of
+ *	H5C1_auto_size_ctl_t passed to the cache must have a known
+ *	version number, or an error will be flagged.
+ *
+ * report_fcn:  Pointer to the function that is to be called to report
+ *      activities each time the auto cache resize code is executed.  If the
+ *	field is NULL, no call is made.
+ *
+ *	If the field is not NULL, it must contain the address of a function
+ *	of type H5C1_auto_resize_report_fcn.
+ *
+ * set_initial_size: Boolean flag indicating whether the size of the
+ *	initial size of the cache is to be set to the value given in
+ *	the initial_size field.  If set_initial_size is FALSE, the
+ *	initial_size field is ignored.
+ *
+ * initial_size: If enabled, this field contain the size the cache is
+ *	to be set to upon receipt of this structure.  Needless to say,
+ *	initial_size must lie in the closed interval [min_size, max_size].
+ *
+ * min_clean_fraction: double in the range 0 to 1 indicating the fraction
+ *	of the cache that is to be kept clean.  This field is only used
+ *	in parallel mode.  Typical values are 0.1 to 0.5.
+ *
+ * max_size: Maximum size to which the cache can be adjusted.  The
+ *	supplied value must fall in the closed interval
+ *	[MIN_MAX_CACHE_SIZE, MAX_MAX_CACHE_SIZE].  Also, max_size must
+ *	be greater than or equal to min_size.
+ *
+ * min_size: Minimum size to which the cache can be adjusted.  The
+ *      supplied value must fall in the closed interval
+ *      [MIN_MAX_CACHE_SIZE, MAX_MAX_CACHE_SIZE].  Also, min_size must
+ *	be less than or equal to max_size.
+ *
+ * epoch_length: Number of accesses on the cache over which to collect
+ *	hit rate stats before running the automatic cache resize code,
+ *      if it is enabled.
+ *
+ *	At the end of an epoch, we discard prior hit rate data and start
+ * 	collecting afresh.  The epoch_length must lie in the closed
+ *	interval [H5C1__MIN_AR_EPOCH_LENGTH, H5C1__MAX_AR_EPOCH_LENGTH].
+ *
+ *
+ * Cache size increase control fields:
+ *
+ * incr_mode: Instance of the H5C1_cache_incr_mode enumerated type whose
+ *	value indicates how we determine whether the cache size should be
+ *	increased.  At present there are two possible values:
+ *
+ *	H5C1_incr__off:	Don't attempt to increase the size of the cache
+ *		automatically.
+ *
+ *		When this increment mode is selected, the remaining fields
+ *		in the cache size increase section ar ignored.
+ *
+ *	H5C1_incr__threshold: Attempt to increase the size of the cache
+ *		whenever the average hit rate over the last epoch drops
+ *		below the value supplied in the lower_hr_threshold
+ *		field.
+ *
+ *		Note that this attempt will fail if the cache is already
+ *		at its maximum size, or if the cache is not already using
+ *		all available space.
+ *
+ * lower_hr_threshold: Lower hit rate threshold.  If the increment mode
+ *	(incr_mode) is H5C1_incr__threshold and the hit rate drops below the
+ *	value supplied in this field in an epoch, increment the cache size by
+ *	size_increment.  Note that cache size may not be incremented above
+ *	max_size, and that the increment may be further restricted by the
+ *	max_increment field if it is enabled.
+ *
+ *	When enabled, this field must contain a value in the range [0.0, 1.0].
+ *	Depending on the incr_mode selected, it may also have to be less than
+ *	upper_hr_threshold.
+ *
+ * increment:  Double containing the multiplier used to derive the new
+ *	cache size from the old if a cache size increment is triggered.
+ *      The increment must be greater than 1.0, and should not exceed 2.0.
+ *
+ *	The new cache size is obtained by multiplying the current max cache
+ *	size by the increment, and then clamping to max_size and to stay
+ *	within the max_increment as necessary.
+ *
+ * apply_max_increment:  Boolean flag indicating whether the max_increment
+ *	field should be used to limit the maximum cache size increment.
+ *
+ * max_increment: If enabled by the apply_max_increment field described
+ *	above, this field contains the maximum number of bytes by which the
+ *	cache size can be increased in a single re-size.
+ *
+ * flash_incr_mode:  Instance of the H5C1_cache_flash_incr_mode enumerated
+ * 	type whose value indicates whether and by what algorithm we should
+ * 	make flash increases in the size of the cache to accomodate insertion
+ * 	of large entries and large increases in the size of a single entry.
+ *
+ * 	The addition of the flash increment mode was occasioned by performance
+ * 	problems that appear when a local heap is increased to a size in excess
+ * 	of the current cache size.  While the existing re-size code dealt with
+ * 	this eventually, performance was very bad for the remainder of the
+ * 	epoch.
+ *
+ * 	At present, there are two possible values for the flash_incr_mode:
+ *
+ * 	H5C1_flash_incr__off:  Don't perform flash increases in the size of
+ * 		the cache.
+ *
+ *	H5C1_flash_incr__add_space:  Let x be either the size of a newly
+ *	        newly inserted entry, or the number of bytes by which the
+ *	        size of an existing entry has been increased.
+ *
+ *	        If
+ *	        	x > flash_threshold * current max cache size,
+ *
+ *	       	increase the current maximum cache size by x * flash_multiple
+ *	       	less any free space in the cache, and start a new epoch.  For
+ *	       	now at least, pay no attention to the maximum increment.
+ *
+ *
+ *	With a little thought, it should be obvious that the above flash
+ *	cache size increase algorithm is not sufficient for all circumstances --
+ *	for example, suppose the user round robins through
+ *	(1/flash_threshold) +1 groups, adding one data set to each on each
+ *	pass.  Then all will increase in size at about the same time, requiring
+ *	the max cache size to at least double to maintain acceptable
+ *      performance, however the above flash increment algorithm will not be
+ *	triggered.
+ *
+ *	Hopefully, the add space algorithm detailed above will be sufficient
+ *	for the performance problems encountered to date.  However, we should
+ *	expect to revisit the issue.
+ *
+ * flash_multiple: Double containing the multiple described above in the
+ * 	H5C1_flash_incr__add_space section of the discussion of the
+ * 	flash_incr_mode	section.  This field is ignored unless flash_incr_mode
+ * 	is H5C1_flash_incr__add_space.
+ *
+ * flash_threshold: Double containing the factor by which current max cache size
+ *      is multiplied to obtain the size threshold for the add_space flash
+ *      increment algorithm.  The field is ignored unless flash_incr_mode is
+ *	H5C1_flash_incr__add_space.
+ *
+ *
+ * Cache size decrease control fields:
+ *
+ * decr_mode: Instance of the H5C1_cache_decr_mode enumerated type whose
+ *	value indicates how we determine whether the cache size should be
+ *	decreased.  At present there are four possibilities.
+ *
+ *	H5C1_decr__off:	Don't attempt to decrease the size of the cache
+ *		automatically.
+ *
+ *		When this increment mode is selected, the remaining fields
+ *		in the cache size decrease section are ignored.
+ *
+ *	H5C1_decr__threshold: Attempt to decrease the size of the cache
+ *		whenever the average hit rate over the last epoch rises
+ *		above the value	supplied in the upper_hr_threshold
+ *		field.
+ *
+ *	H5C1_decr__age_out:  At the end of each epoch, search the cache for
+ *		entries that have not been accessed for at least the number
+ *		of epochs specified in the epochs_before_eviction field, and
+ *		evict these entries.  Conceptually, the maximum cache size
+ *		is then decreased to match the new actual cache size.  However,
+ *		this reduction may be modified by the min_size, the
+ *		max_decrement, and/or the empty_reserve.
+ *
+ *	H5C1_decr__age_out_with_threshold:  Same as age_out, but we only
+ *		attempt to reduce the cache size when the hit rate observed
+ *		over the last epoch exceeds the value provided in the
+ *		upper_hr_threshold field.
+ *
+ * upper_hr_threshold: Upper hit rate threshold.  The use of this field
+ *	varies according to the current decr_mode:
+ *
+ *	H5C1_decr__off or H5C1_decr__age_out:  The value of this field is
+ *		ignored.
+ *
+ *	H5C1_decr__threshold:  If the hit rate exceeds this threshold in any
+ *		epoch, attempt to decrement the cache size by size_decrement.
+ *
+ *		Note that cache size may not be decremented below min_size.
+ *
+ *		Note also that if the upper_threshold is 1.0, the cache size
+ *		will never be reduced.
+ *
+ *	H5C1_decr__age_out_with_threshold:  If the hit rate exceeds this
+ *		threshold in any epoch, attempt to reduce the cache size
+ *		by evicting entries that have not been accessed for more
+ *		than the specified number of epochs.
+ *
+ * decrement: This field is only used when the decr_mode is
+ *	H5C1_decr__threshold.
+ *
+ *	The field is a double containing the multiplier used to derive the
+ *	new cache size from the old if a cache size decrement is triggered.
+ *	The decrement must be in the range 0.0 (in which case the cache will
+ *      try to contract to its minimum size) to 1.0 (in which case the
+ *      cache will never shrink).
+ *
+ * apply_max_decrement:  Boolean flag used to determine whether decrements
+ *	in cache size are to be limited by the max_decrement field.
+ *
+ * max_decrement: Maximum number of bytes by which the cache size can be
+ *	decreased in a single re-size.  Note that decrements may also be
+ *	restricted by the min_size of the cache, and (in age out modes) by
+ *	the empty_reserve field.
+ *
+ * epochs_before_eviction:  Integer field used in H5C1_decr__age_out and
+ *	H5C1_decr__age_out_with_threshold decrement modes.
+ *
+ *	This field contains the number of epochs an entry must remain
+ *	unaccessed before it is evicted in an attempt to reduce the
+ *	cache size.  If applicable, this field must lie in the range
+ *	[1, H5C1__MAX_EPOCH_MARKERS].
+ *
+ * apply_empty_reserve:  Boolean field controlling whether the empty_reserve
+ *	field is to be used in computing the new cache size when the
+ *	decr_mode is H5C1_decr__age_out or H5C1_decr__age_out_with_threshold.
+ *
+ * empty_reserve:  To avoid a constant racheting down of cache size by small
+ *	amounts in the H5C1_decr__age_out and H5C1_decr__age_out_with_threshold
+ *	modes, this field allows one to require that any cache size
+ *	reductions leave the specified fraction of unused space in the cache.
+ *
+ *	The value of this field must be in the range [0.0, 1.0].  I would
+ *	expect typical values to be in the range of 0.01 to 0.1.
+ *
+ ****************************************************************************/
+
+#define H5C1_RESIZE_CFG__VALIDATE_GENERAL        0x1
+#define H5C1_RESIZE_CFG__VALIDATE_INCREMENT      0x2
+#define H5C1_RESIZE_CFG__VALIDATE_DECREMENT      0x4
+#define H5C1_RESIZE_CFG__VALIDATE_INTERACTIONS   0x8
+#define H5C1_RESIZE_CFG__VALIDATE_ALL      \
+(                                         \
+    H5C1_RESIZE_CFG__VALIDATE_GENERAL |    \
+    H5C1_RESIZE_CFG__VALIDATE_INCREMENT |  \
+    H5C1_RESIZE_CFG__VALIDATE_DECREMENT |  \
+    H5C1_RESIZE_CFG__VALIDATE_INTERACTIONS \
+)
+
+#define H5C1__CURR_AUTO_SIZE_CTL_VER		1
+#define H5C1__CURR_AUTO_RESIZE_RPT_FCN_VER	1
+
+#define H5C1__MAX_EPOCH_MARKERS  		10
+
+#define H5C1__DEF_AR_UPPER_THRESHHOLD		0.9999
+#define H5C1__DEF_AR_LOWER_THRESHHOLD		0.9
+#define H5C1__DEF_AR_MAX_SIZE			((size_t)(16 * 1024 * 1024))
+#define H5C1__DEF_AR_INIT_SIZE			((size_t)( 1 * 1024 * 1024))
+#define H5C1__DEF_AR_MIN_SIZE			((size_t)( 1 * 1024 * 1024))
+#define H5C1__DEF_AR_MIN_CLEAN_FRAC		0.5
+#define H5C1__DEF_AR_INCREMENT			2.0
+#define H5C1__DEF_AR_MAX_INCREMENT		((size_t)( 2 * 1024 * 1024))
+#define	H5C1__DEF_AR_FLASH_MULTIPLE		1.0
+#define H5C1__DEV_AR_FLASH_THRESHOLD		0.25
+#define H5C1__DEF_AR_DECREMENT			0.9
+#define H5C1__DEF_AR_MAX_DECREMENT		((size_t)( 1 * 1024 * 1024))
+#define H5C1__DEF_AR_EPCHS_B4_EVICT		3
+#define H5C1__DEF_AR_EMPTY_RESERVE		0.05
+#define H5C1__MIN_AR_EPOCH_LENGTH		100
+#define H5C1__DEF_AR_EPOCH_LENGTH		50000
+#define H5C1__MAX_AR_EPOCH_LENGTH		1000000
+
+enum H5C1_resize_status
+{
+    in_spec,
+    increase,
+    flash_increase,
+    decrease,
+    at_max_size,
+    at_min_size,
+    increase_disabled,
+    decrease_disabled,
+    not_full
+}; /* enum H5C1_resize_conditions */
+
+typedef void (*H5C1_auto_resize_rpt_fcn)(H5C1_t * cache_ptr,
+                                        int32_t version,
+                                        double hit_rate,
+                                        enum H5C1_resize_status status,
+                                        size_t old_max_cache_size,
+                                        size_t new_max_cache_size,
+                                        size_t old_min_clean_size,
+                                        size_t new_min_clean_size);
+
+typedef struct H5C1_auto_size_ctl_t
+{
+    /* general configuration fields: */
+    int32_t				version;
+    H5C1_auto_resize_rpt_fcn		rpt_fcn;
+
+    hbool_t				set_initial_size;
+    size_t				initial_size;
+
+    double				min_clean_fraction;
+
+    size_t				max_size;
+    size_t				min_size;
+
+    int64_t				epoch_length;
+
+
+    /* size increase control fields: */
+    enum H5C1_cache_incr_mode		incr_mode;
+
+    double				lower_hr_threshold;
+
+    double				increment;
+
+    hbool_t				apply_max_increment;
+    size_t				max_increment;
+
+    enum H5C1_cache_flash_incr_mode	flash_incr_mode;
+    double				flash_multiple;
+    double				flash_threshold;
+
+    /* size decrease control fields: */
+    enum H5C1_cache_decr_mode		decr_mode;
+
+    double				upper_hr_threshold;
+
+    double				decrement;
+
+    hbool_t				apply_max_decrement;
+    size_t				max_decrement;
+
+    int32_t				epochs_before_eviction;
+
+    hbool_t				apply_empty_reserve;
+    double				empty_reserve;
+
+} H5C1_auto_size_ctl_t;
+
+
+/*
+ * Library prototypes.
+ */
+
+/* #defines of flags used in the flags parameters in some of the
+ * following function calls.  Note that not all flags are applicable
+ * to all function calls.  Flags that don't apply to a particular
+ * function are ignored in that function.
+ *
+ * These flags apply to all function calls:
+ *
+ * 	H5C1__NO_FLAGS_SET (generic "no flags set" for all fcn calls)
+ *
+ *
+ * These flags apply to H5C1_insert_entry():
+ *
+ * 	H5C1__SET_FLUSH_MARKER_FLAG
+ * 	H5C1__PIN_ENTRY_FLAG
+ *
+ * These flags apply to H5C1_protect()
+ *
+ * 	H5C1__READ_ONLY_FLAG
+ *
+ * These flags apply to H5C1_unprotect():
+ *
+ * 	H5C1__SET_FLUSH_MARKER_FLAG
+ * 	H5C1__DELETED_FLAG
+ * 	H5C1__DIRTIED_FLAG
+ * 	H5C1__SIZE_CHANGED_FLAG
+ * 	H5C1__PIN_ENTRY_FLAG
+ * 	H5C1__UNPIN_ENTRY_FLAG
+ *
+ *
+ * These flags apply to H5C1_flush_cache():
+ *
+ * 	H5C1__FLUSH_INVALIDATE_FLAG
+ * 	H5C1__FLUSH_CLEAR_ONLY_FLAG
+ * 	H5C1__FLUSH_MARKED_ENTRIES_FLAG
+ *	H5C1__FLUSH_IGNORE_PROTECTED_FLAG (can't use this flag in combination
+ *					  with H5C1__FLUSH_INVALIDATE_FLAG)
+ *
+ * These flags apply to H5C1_flush_single_entry():
+ *
+ * 	H5C1__FLUSH_INVALIDATE_FLAG
+ * 	H5C1__FLUSH_CLEAR_ONLY_FLAG
+ * 	H5C1__FLUSH_MARKED_ENTRIES_FLAG
+ */
+
+#define H5C1__NO_FLAGS_SET			0x0000
+#define H5C1__SET_FLUSH_MARKER_FLAG		0x0001
+#define H5C1__DELETED_FLAG			0x0002
+#define H5C1__DIRTIED_FLAG			0x0004
+#define H5C1__SIZE_CHANGED_FLAG			0x0008
+#define H5C1__PIN_ENTRY_FLAG			0x0010
+#define H5C1__UNPIN_ENTRY_FLAG			0x0020
+#define H5C1__FLUSH_INVALIDATE_FLAG		0x0040
+#define H5C1__FLUSH_CLEAR_ONLY_FLAG		0x0080
+#define H5C1__FLUSH_MARKED_ENTRIES_FLAG		0x0100
+#define H5C1__FLUSH_IGNORE_PROTECTED_FLAG	0x0200
+#define H5C1__READ_ONLY_FLAG			0x0400
+
+
+H5_DLL H5C1_t * H5C1_create(size_t                     max_cache_size,
+                          size_t                     min_clean_size,
+                          int                        max_type_id,
+                          const char *               (* type_name_table_ptr),
+                          H5C1_write_permitted_func_t check_write_permitted,
+                          hbool_t		     write_permitted,
+                          H5C1_log_flush_func_t       log_flush,
+                          void *                     aux_ptr);
+
+H5_DLL void H5C1_def_auto_resize_rpt_fcn(H5C1_t * cache_ptr,
+                                        int32_t version,
+                                        double hit_rate,
+                                        enum H5C1_resize_status status,
+                                        size_t old_max_cache_size,
+                                        size_t new_max_cache_size,
+                                        size_t old_min_clean_size,
+                                        size_t new_min_clean_size);
+
+H5_DLL herr_t H5C1_dest(H5F_t * f,
+                       hid_t   primary_dxpl_id,
+                       hid_t   secondary_dxpl_id,
+                       H5C1_t * cache_ptr);
+
+H5_DLL herr_t H5C1_dest_empty(H5C1_t * cache_ptr);
+
+H5_DLL herr_t H5C1_expunge_entry(H5F_t *             f,
+		                hid_t               primary_dxpl_id,
+                                hid_t               secondary_dxpl_id,
+                                H5C1_t *             cache_ptr,
+                                const H5C1_class_t * type,
+                                haddr_t             addr);
+
+H5_DLL herr_t H5C1_flush_cache(H5F_t *  f,
+                              hid_t    primary_dxpl_id,
+                              hid_t    secondary_dxpl_id,
+                              H5C1_t *  cache_ptr,
+                              unsigned flags);
+
+H5_DLL herr_t H5C1_flush_to_min_clean(H5F_t * f,
+                                     hid_t   primary_dxpl_id,
+                                     hid_t   secondary_dxpl_id,
+                                     H5C1_t * cache_ptr);
+
+H5_DLL herr_t H5C1_get_cache_auto_resize_config(H5C1_t * cache_ptr,
+                                               H5C1_auto_size_ctl_t *config_ptr);
+
+H5_DLL herr_t H5C1_get_cache_size(H5C1_t * cache_ptr,
+                                 size_t * max_size_ptr,
+                                 size_t * min_clean_size_ptr,
+                                 size_t * cur_size_ptr,
+                                 int32_t * cur_num_entries_ptr);
+
+H5_DLL herr_t H5C1_get_cache_hit_rate(H5C1_t * cache_ptr,
+                                     double * hit_rate_ptr);
+
+H5_DLL herr_t H5C1_get_entry_status(H5C1_t *   cache_ptr,
+                                   haddr_t   addr,
+                                   size_t *  size_ptr,
+                                   hbool_t * in_cache_ptr,
+                                   hbool_t * is_dirty_ptr,
+                                   hbool_t * is_protected_ptr,
+				   hbool_t * is_pinned_ptr);
+
+H5_DLL herr_t H5C1_get_evictions_enabled(H5C1_t * cache_ptr,
+                                        hbool_t * evictions_enabled_ptr);
+
+H5_DLL herr_t H5C1_get_trace_file_ptr(H5C1_t * cache_ptr,
+		                     FILE ** trace_file_ptr_ptr);
+
+H5_DLL herr_t H5C1_insert_entry(H5F_t *             f,
+                               hid_t               primary_dxpl_id,
+                               hid_t               secondary_dxpl_id,
+                               H5C1_t *             cache_ptr,
+                               const H5C1_class_t * type,
+                               haddr_t             addr,
+                               void *              thing,
+                               unsigned int        flags);
+
+H5_DLL herr_t H5C1_mark_entries_as_clean(H5F_t   * f,
+                                        hid_t     primary_dxpl_id,
+                                        hid_t     secondary_dxpl_id,
+                                        H5C1_t   * cache_ptr,
+                                        int32_t   ce_array_len,
+                                        haddr_t * ce_array_ptr);
+
+H5_DLL herr_t H5C1_mark_pinned_entry_dirty(H5C1_t * cache_ptr,
+	                                  void *  thing,
+					  hbool_t size_changed,
+					  size_t  new_size);
+
+H5_DLL herr_t H5C1_mark_pinned_or_protected_entry_dirty(H5C1_t * cache_ptr,
+                                                       void *  thing);
+
+H5_DLL herr_t H5C1_rename_entry(H5C1_t *             cache_ptr,
+                               const H5C1_class_t * type,
+                               haddr_t             old_addr,
+                               haddr_t             new_addr);
+
+H5_DLL herr_t H5C1_pin_protected_entry(H5C1_t * cache_ptr,
+                                      void *  thing);
+
+H5_DLL void * H5C1_protect(H5F_t *             f,
+                          hid_t               primary_dxpl_id,
+                          hid_t               secondary_dxpl_id,
+                          H5C1_t *             cache_ptr,
+                          const H5C1_class_t * type,
+                          haddr_t             addr,
+                          const void *        udata1,
+                          void *              udata2,
+			  unsigned            flags);
+
+H5_DLL herr_t H5C1_reset_cache_hit_rate_stats(H5C1_t * cache_ptr);
+
+H5_DLL herr_t H5C1_resize_pinned_entry(H5C1_t * cache_ptr,
+                                      void *  thing,
+                                      size_t  new_size);
+
+H5_DLL herr_t H5C1_set_cache_auto_resize_config(H5C1_t * cache_ptr,
+                                               H5C1_auto_size_ctl_t *config_ptr);
+
+H5_DLL herr_t H5C1_set_evictions_enabled(H5C1_t * cache_ptr,
+                                        hbool_t evictions_enabled);
+
+H5_DLL herr_t H5C1_set_prefix(H5C1_t * cache_ptr, char * prefix);
+
+H5_DLL herr_t H5C1_set_skip_flags(H5C1_t * cache_ptr,
+                                 hbool_t skip_file_checks,
+                                 hbool_t skip_dxpl_id_checks);
+
+H5_DLL herr_t H5C1_set_trace_file_ptr(H5C1_t * cache_ptr,
+		                     FILE * trace_file_ptr);
+
+H5_DLL herr_t H5C1_stats(H5C1_t * cache_ptr,
+                        const char * cache_name,
+                        hbool_t display_detailed_stats);
+
+H5_DLL void H5C1_stats__reset(H5C1_t * cache_ptr);
+
+H5_DLL herr_t H5C1_unpin_entry(H5C1_t * cache_ptr, void * thing);
+
+H5_DLL herr_t H5C1_unprotect(H5F_t *             f,
+                            hid_t               primary_dxpl_id,
+                            hid_t               secondary_dxpl_id,
+                            H5C1_t *             cache_ptr,
+                            const H5C1_class_t * type,
+                            haddr_t             addr,
+                            void *              thing,
+                            unsigned int        flags,
+                            size_t              new_size);
+
+H5_DLL herr_t H5C1_validate_resize_config(H5C1_auto_size_ctl_t * config_ptr,
+                                         unsigned int tests);
+
+#endif /* !_H5C1private_H */
+