diff options
Diffstat (limited to 'src/H5Cpkg.h')
| -rw-r--r-- | src/H5Cpkg.h | 582 |
1 files changed, 75 insertions, 507 deletions
diff --git a/src/H5Cpkg.h b/src/H5Cpkg.h index 23c2b78..24c0263 100644 --- a/src/H5Cpkg.h +++ b/src/H5Cpkg.h @@ -83,89 +83,6 @@ * to the HGOTO_ERROR macro, which may not be appropriate in all cases. * If so, we will need versions of the insertion and deletion macros which * do not reference the sanity checking macros. - * JRM - 5/5/04 - * - * Changes: - * - * - Removed the line: - * - * ( ( (Size) == (entry_ptr)->size ) && ( (len) != 1 ) ) || - * - * from the H5C__DLL_PRE_REMOVE_SC macro. With the addition of the - * epoch markers used in the age out based cache size reduction algorithm, - * this invariant need not hold, as the epoch markers are of size 0. - * - * One could argue that I should have given the epoch markers a positive - * size, but this would break the index_size = LRU_list_size + pl_size - * + pel_size invariant. - * - * Alternatively, I could pass the current decr_mode in to the macro, - * and just skip the check whenever epoch markers may be in use. - * - * However, any size errors should be caught when the cache is flushed - * and destroyed. Until we are tracking such an error, this should be - * good enough. - * JRM - 12/9/04 - * - * - * - In the H5C__DLL_PRE_INSERT_SC macro, replaced the lines: - * - * ( ( (len) == 1 ) && - * ( ( (head_ptr) != (tail_ptr) ) || ( (Size) <= 0 ) || - * ( (head_ptr) == NULL ) || ( (head_ptr)->size != (Size) ) - * ) - * ) || - * - * with: - * - * ( ( (len) == 1 ) && - * ( ( (head_ptr) != (tail_ptr) ) || - * ( (head_ptr) == NULL ) || ( (head_ptr)->size != (Size) ) - * ) - * ) || - * - * Epoch markers have size 0, so we can now have a non-empty list with - * zero size. Hence the "( (Size) <= 0 )" clause cause false failures - * in the sanity check. Since "Size" is typically a size_t, it can't - * take on negative values, and thus the revised clause "( (Size) < 0 )" - * caused compiler warnings. - * JRM - 12/22/04 - * - * - In the H5C__DLL_SC macro, replaced the lines: - * - * ( ( (len) == 1 ) && - * ( ( (head_ptr) != (tail_ptr) ) || ( (cache_ptr)->size <= 0 ) || - * ( (head_ptr) == NULL ) || ( (head_ptr)->size != (Size) ) - * ) - * ) || - * - * with - * - * ( ( (len) == 1 ) && - * ( ( (head_ptr) != (tail_ptr) ) || - * ( (head_ptr) == NULL ) || ( (head_ptr)->size != (Size) ) - * ) - * ) || - * - * Epoch markers have size 0, so we can now have a non-empty list with - * zero size. Hence the "( (Size) <= 0 )" clause cause false failures - * in the sanity check. Since "Size" is typically a size_t, it can't - * take on negative values, and thus the revised clause "( (Size) < 0 )" - * caused compiler warnings. - * JRM - 1/10/05 - * - * - Added the H5C__DLL_UPDATE_FOR_SIZE_CHANGE macro and the associated - * sanity checking macros. These macro are used to update the size of - * a DLL when one of its entries changes size. - * - * JRM - 9/8/05 - * - * - Added macros supporting the index list -- a doubly liked list of - * all entries in the index. This list is necessary to reduce the - * cost of visiting all entries in the cache, which was previously - * done via a scan of the hash table. - * - * JRM - 10/15/15 * ****************************************************************************/ @@ -966,28 +883,6 @@ if ( ( ( ( (head_ptr) == NULL ) || ( (tail_ptr) == NULL ) ) && \ * When modifying these macros, remember to modify the similar macros * in tst/cache.c * - * Changes: - * - * - Updated existing index macros and sanity check macros to maintain - * the clean_index_size and dirty_index_size fields of H5C_t. Also - * added macros to allow us to track entry cleans and dirties. - * - * JRM -- 11/5/08 - * - * - Updated existing index macros and sanity check macros to maintain - * the index_ring_len, index_ring_size, clean_index_ring_size, and - * dirty_index_ring_size fields of H5C_t. - * - * JRM -- 9/1/15 - * - * - Updated existing index macros and sanity checks macros to - * maintain an doubly linked list of all entries in the index. - * This is necessary to reduce the computational cost of visiting - * all entries in the index, which used to be done by scanning - * the hash table. - * - * JRM -- 10/15/15 - * ***********************************************************************/ /* H5C__HASH_TABLE_LEN is defined in H5Cpkg.h. It mut be a power of two. */ @@ -1518,9 +1413,6 @@ if ( ( (cache_ptr)->index_size != \ * * Skip list insertion and deletion macros: * - * These used to be functions, but I converted them to macros to avoid some - * function call overhead. - * **************************************************************************/ /*------------------------------------------------------------------------- @@ -1535,56 +1427,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 5/10/04 * - * Modifications: - * - * JRM -- 7/21/04 - * Updated function to set the in_tree flag when inserting - * an entry into the tree. Also modified the function to - * update the tree size and len fields instead of the similar - * index fields. - * - * All of this is part of the modifications to support the - * hash table. - * - * JRM -- 7/27/04 - * Converted the function H5C_insert_entry_in_tree() into - * the macro H5C__INSERT_ENTRY_IN_TREE in the hopes of - * wringing a little more speed out of the cache. - * - * Note that we don't bother to check if the entry is already - * in the tree -- if it is, H5SL_insert() will fail. - * - * QAK -- 11/27/04 - * Switched over to using skip list routines. - * - * JRM -- 6/27/06 - * Added fail_val parameter. - * - * JRM -- 8/25/06 - * Added the H5C_DO_SANITY_CHECKS version of the macro. - * - * This version maintains the slist_len_increase and - * slist_size_increase fields that are used in sanity - * checks in the flush routines. - * - * All this is needed as the fractal heap needs to be - * able to dirty, resize and/or move entries during the - * flush. - * - * JRM -- 12/13/14 - * Added code to set cache_ptr->slist_changed to TRUE - * when an entry is inserted in the slist. - * - * JRM -- 9/1/15 - * Added code to maintain the cache_ptr->slist_ring_len - * and cache_ptr->slist_ring_size arrays. - * - * JRM -- 4/29/20 - * Reworked macro to support the slist_enabled field - * of H5C_t. If slist_enabled == TRUE, the macro - * functions as before. Otherwise, the macro is a no-op, - * and the slist must be empty. - * *------------------------------------------------------------------------- */ @@ -1716,33 +1558,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 5/10/04 * - * Modifications: - * - * JRM -- 7/21/04 - * Updated function for the addition of the hash table. - * - * JRM - 7/27/04 - * Converted from the function H5C_remove_entry_from_tree() - * to the macro H5C__REMOVE_ENTRY_FROM_TREE in the hopes of - * wringing a little more performance out of the cache. - * - * QAK -- 11/27/04 - * Switched over to using skip list routines. - * - * JRM -- 3/28/07 - * Updated sanity checks for the new is_read_only and - * ro_ref_count fields in H5C_cache_entry_t. - * - * JRM -- 12/13/14 - * Added code to set cache_ptr->slist_changed to TRUE - * when an entry is removed from the slist. - * - * JRM -- 4/29/20 - * Reworked macro to support the slist_enabled field - * of H5C_t. If slist_enabled == TRUE, the macro - * functions as before. Otherwise, the macro is a no-op, - * and the slist must be empty. - * *------------------------------------------------------------------------- */ @@ -1853,33 +1668,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 9/07/05 * - * Modifications: - * - * JRM -- 8/27/06 - * Added the H5C_DO_SANITY_CHECKS version of the macro. - * - * This version maintains the slist_size_increase field - * that are used in sanity checks in the flush routines. - * - * All this is needed as the fractal heap needs to be - * able to dirty, resize and/or move entries during the - * flush. - * - * JRM -- 12/13/14 - * Note that we do not set cache_ptr->slist_changed to TRUE - * in this case, as the structure of the slist is not - * modified. - * - * JRM -- 9/1/15 - * Added code to maintain the cache_ptr->slist_ring_len - * and cache_ptr->slist_ring_size arrays. - * - * JRM -- 4/29/20 - * Reworked macro to support the slist_enabled field - * of H5C_t. If slist_enabled == TRUE, the macro - * functions as before. Otherwise, the macro is a no-op, - * and the slist must be empty. - * *------------------------------------------------------------------------- */ @@ -1976,9 +1764,6 @@ if ( ( (cache_ptr)->index_size != \ * * Replacement policy update macros: * - * These used to be functions, but I converted them to macros to avoid some - * function call overhead. - * **************************************************************************/ /*------------------------------------------------------------------------- @@ -2000,18 +1785,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 10/13/05 * - * Modifications: - * - * JRM -- 3/20/06 - * Modified macro to ignore pinned entries. Pinned entries - * do not appear in the data structures maintained by the - * replacement policy code, and thus this macro has nothing - * to do if called for such an entry. - * - * JRM -- 3/28/07 - * Added sanity checks using the new is_read_only and - * ro_ref_count fields of struct H5C_cache_entry_t. - * *------------------------------------------------------------------------- */ @@ -2130,30 +1903,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 5/10/04 * - * Modifications: - * - * JRM - 7/27/04 - * Converted the function H5C_update_rp_for_eviction() to the - * macro H5C__UPDATE_RP_FOR_EVICTION in an effort to squeeze - * a bit more performance out of the cache. - * - * At least for the first cut, I am leaving the comments and - * white space in the macro. If they cause difficulties with - * the pre-processor, I'll have to remove them. - * - * JRM - 7/28/04 - * Split macro into two version, one supporting the clean and - * dirty LRU lists, and the other not. Yet another attempt - * at optimization. - * - * JRM - 3/20/06 - * Pinned entries can't be evicted, so this entry should never - * be called on a pinned entry. Added assert to verify this. - * - * JRM -- 3/28/07 - * Added sanity checks for the new is_read_only and - * ro_ref_count fields of struct H5C_cache_entry_t. - * *------------------------------------------------------------------------- */ @@ -2241,32 +1990,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 5/6/04 * - * Modifications: - * - * JRM - 7/27/04 - * Converted the function H5C_update_rp_for_flush() to the - * macro H5C__UPDATE_RP_FOR_FLUSH in an effort to squeeze - * a bit more performance out of the cache. - * - * At least for the first cut, I am leaving the comments and - * white space in the macro. If they cause difficulties with - * pre-processor, I'll have to remove them. - * - * JRM - 7/28/04 - * Split macro into two versions, one supporting the clean and - * dirty LRU lists, and the other not. Yet another attempt - * at optimization. - * - * JRM - 3/20/06 - * While pinned entries can be flushed, they don't reside in - * the replacement policy data structures when unprotected. - * Thus I modified this macro to do nothing if the entry is - * pinned. - * - * JRM - 3/28/07 - * Added sanity checks based on the new is_read_only and - * ro_ref_count fields of struct H5C_cache_entry_t. - * *------------------------------------------------------------------------- */ @@ -2499,34 +2222,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 5/17/04 * - * Modifications: - * - * JRM - 7/27/04 - * Converted the function H5C_update_rp_for_insertion() to the - * macro H5C__UPDATE_RP_FOR_INSERTION in an effort to squeeze - * a bit more performance out of the cache. - * - * At least for the first cut, I am leaving the comments and - * white space in the macro. If they cause difficulties with - * pre-processor, I'll have to remove them. - * - * JRM - 7/28/04 - * Split macro into two version, one supporting the clean and - * dirty LRU lists, and the other not. Yet another attempt - * at optimization. - * - * JRM - 3/10/06 - * This macro should never be called on a pinned entry. - * Inserted an assert to verify this. - * - * JRM - 8/9/06 - * Not any more. We must now allow insertion of pinned - * entries. Updated macro to support this. - * - * JRM - 3/28/07 - * Added sanity checks using the new is_read_only and - * ro_ref_count fields of struct H5C_cache_entry_t. - * *------------------------------------------------------------------------- */ @@ -2637,31 +2332,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 5/17/04 * - * Modifications: - * - * JRM - 7/27/04 - * Converted the function H5C_update_rp_for_protect() to the - * macro H5C__UPDATE_RP_FOR_PROTECT in an effort to squeeze - * a bit more performance out of the cache. - * - * At least for the first cut, I am leaving the comments and - * white space in the macro. If they cause difficulties with - * pre-processor, I'll have to remove them. - * - * JRM - 7/28/04 - * Split macro into two version, one supporting the clean and - * dirty LRU lists, and the other not. Yet another attempt - * at optimization. - * - * JRM - 3/17/06 - * Modified macro to attempt to remove pinned entriese from - * the pinned entry list instead of from the data structures - * maintained by the replacement policy. - * - * JRM - 3/28/07 - * Added sanity checks based on the new is_read_only and - * ro_ref_count fields of struct H5C_cache_entry_t. - * *------------------------------------------------------------------------- */ @@ -2927,12 +2597,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 8/23/06 * - * Modifications: - * - * JRM -- 3/28/07 - * Added sanity checks based on the new is_read_only and - * ro_ref_count fields of struct H5C_cache_entry_t. - * *------------------------------------------------------------------------- */ @@ -3060,12 +2724,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 3/22/06 * - * Modifications: - * - * JRM -- 3/28/07 - * Added sanity checks based on the new is_read_only and - * ro_ref_count fields of struct H5C_cache_entry_t. - * *------------------------------------------------------------------------- */ @@ -3181,27 +2839,6 @@ if ( ( (cache_ptr)->index_size != \ * * Programmer: John Mainzer, 5/19/04 * - * Modifications: - * - * JRM - 7/27/04 - * Converted the function H5C_update_rp_for_unprotect() to - * the macro H5C__UPDATE_RP_FOR_UNPROTECT in an effort to - * squeeze a bit more performance out of the cache. - * - * At least for the first cut, I am leaving the comments and - * white space in the macro. If they cause difficulties with - * pre-processor, I'll have to remove them. - * - * JRM - 7/28/04 - * Split macro into two version, one supporting the clean and - * dirty LRU lists, and the other not. Yet another attempt - * at optimization. - * - * JRM - 3/17/06 - * Modified macro to put pinned entries on the pinned entry - * list instead of inserting them in the data structures - * maintained by the replacement policy. - * *------------------------------------------------------------------------- */ @@ -3608,24 +3245,9 @@ typedef struct H5C_tag_info_t { * While the cache was designed with multiple replacement policies in mind, * at present only a modified form of LRU is supported. * - * JRM - 4/26/04 - * - * Profiling has indicated that searches in the instance of H5TB_TREE are - * too expensive. To deal with this issue, I have augmented the cache - * with a hash table in which all entries will be stored. Given the - * advantages of flushing entries in increasing address order, the TBBT - * is retained, but only dirty entries are stored in it. At least for - * now, we will leave entries in the TBBT after they are flushed. - * - * Note that index_size and index_len now refer to the total size of - * and number of entries in the hash table. - * - * JRM - 7/19/04 - * - * The TBBT has since been replaced with a skip list. This change - * greatly predates this note. - * - * JRM - 9/26/05 + * The cache has a hash table in which all entries are stored. Given the + * advantages of flushing entries in increasing address order, a skip list + * is used to track dirty entries. * * magic: Unsigned 32 bit integer always set to H5C__H5C_T_MAGIC. * This field is used to validate pointers to instances of @@ -3719,13 +3341,8 @@ typedef struct H5C_tag_info_t { * The cache requires an index to facilitate searching for entries. The * following fields support that index. * - * Addendum: JRM -- 10/14/15 - * - * We sometimes need to visit all entries in the cache. In the past, this - * was done by scanning the hash table. However, this is expensive, and - * we have come to scan the hash table often enough that it has become a - * performance issue. To repair this, I have added code to maintain a - * list of all entries in the index -- call this list the index list. + * We sometimes need to visit all entries in the cache, they are stored in + * the index list. * * The index list is maintained by the same macros that maintain the * index, and must have the same length and size as the index proper. @@ -3759,12 +3376,10 @@ typedef struct H5C_tag_info_t { * dirty_index_size == index_size. * * WARNING: - * - * The value of the clean_index_size must not be mistaken - * for the current clean size of the cache. Rather, the - * clean size of the cache is the current value of - * clean_index_size plus the amount of empty space (if any) - * in the cache. + * The value of the clean_index_size must not be mistaken for + * the current clean size of the cache. Rather, the clean size + * of the cache is the current value of clean_index_size plus + * the amount of empty space (if any) in the cache. * * clean_index_ring_size: Array of size_t of length H5C_RING_NTYPES used to * maintain the sum of the sizes of all clean entries in the @@ -3786,7 +3401,7 @@ typedef struct H5C_tag_info_t { * H5C__HASH_TABLE_LEN. At present, this value is a power * of two, not the usual prime number. * - * I hope that the variable size of cache elements, the large + * Hopefully the variable size of cache elements, the large * hash table size, and the way in which HDF5 allocates space * will combine to avoid problems with periodicity. If so, we * can use a trivial hash function (a bit-and and a 3 bit left @@ -3827,11 +3442,10 @@ typedef struct H5C_tag_info_t { * This field is NULL if the index is empty. * * - * With the addition of the take ownership flag, it is possible that - * an entry may be removed from the cache as the result of the flush of - * a second entry. In general, this causes little trouble, but it is - * possible that the entry removed may be the next entry in the scan of - * a list. In this case, we must be able to detect the fact that the + * It is possible that an entry may be removed from the cache as the result + * of the flush of a second entry. In general, this causes little trouble, + * but it is possible that the entry removed may be the next entry in the + * scan of a list. In this case, we must be able to detect the fact that the * entry has been removed, so that the scan doesn't attempt to proceed with * an entry that is no longer in the cache. * @@ -3859,29 +3473,19 @@ typedef struct H5C_tag_info_t { * one. * * entry_watched_for_removal: Pointer to an instance of H5C_cache_entry_t - * which contains the 'next' entry for an iteration. Removing - * this entry must trigger a rescan of the iteration, so each - * entry removed from the cache is compared against this pointer - * and the pointer is reset to NULL if the watched entry is - * removed. - * (This functions similarly to a "dead man's switch") + * which contains the 'next' entry for an iteration. Removing + * this entry must trigger a rescan of the iteration, so each + * entry removed from the cache is compared against this pointer + * and the pointer is reset to NULL if the watched entry is + * removed. (This functions similarly to a "dead man's switch") * * * When we flush the cache, we need to write entries out in increasing * address order. An instance of a skip list is used to store dirty entries in - * sorted order. Whether it is cheaper to sort the dirty entries as needed, - * or to maintain the list is an open question. At a guess, it depends - * on how frequently the cache is flushed. We will see how it goes. - * - * For now at least, I will not remove dirty entries from the list as they - * are flushed. (this has been changed -- dirty entries are now removed from - * the skip list as they are flushed. JRM - 10/25/05) - * - * Update 4/21/20: + * sorted order. * - * Profiling indicates that the cost of maintaining the skip list is - * significant. As it is only used on flush and close, maintaining it - * only when needed is an obvious optimization. + * The cost of maintaining the skip list is significant. As it is only used + * on flush and close, it is maintained only when needed. * * To do this, we add a flag to control maintenanace of the skip list. * This flag is initially set to FALSE, which disables all operations @@ -3940,30 +3544,21 @@ typedef struct H5C_tag_info_t { * order, which results in significant savings. * * b) It facilitates checking for adjacent dirty entries when - * attempting to evict entries from the cache. While we - * don't use this at present, I hope that this will allow - * some optimizations when I get to it. + * attempting to evict entries from the cache. * * num_last_entries: The number of entries in the cache that can only be * flushed after all other entries in the cache have - * been flushed. At this time, this will only ever be - * one entry (the superblock), and the code has been - * protected with HDasserts to enforce this. This restraint - * can certainly be relaxed in the future if the need for - * multiple entries being flushed last arises, though - * explicit tests for that case should be added when said - * HDasserts are removed. - * - * Update: There are now two possible last entries - * (superblock and file driver info message). This - * number will probably increase as we add superblock - * messages. JRM -- 11/18/14 - * - * With the addition of the fractal heap, the cache must now deal with - * the case in which entries may be dirtied, moved, or have their sizes - * changed during a flush. To allow sanity checks in this situation, the - * following two fields have been added. They are only compiled in when - * H5C_DO_SANITY_CHECKS is TRUE. + * been flushed. + * + * Note: At this time, the this field will only be applied to + * two types of entries: the superblock and the file driver info + * message. The code utilizing these flags is protected with + * HDasserts to enforce this. + * + * The cache must deal with the case in which entries may be dirtied, moved, + * or have their sizes changed during a flush. To allow sanity checks in this + * situation, the following two fields have been added. They are only + * compiled in when H5C_DO_SANITY_CHECKS is TRUE. * * slist_len_increase: Number of entries that have been added to the * slist since the last time this field was set to zero. @@ -4020,8 +3615,8 @@ typedef struct H5C_tag_info_t { * * * For very frequently used entries, the protect/unprotect overhead can - * become burdensome. To avoid this overhead, I have modified the cache - * to allow entries to be "pinned". A pinned entry is similar to a + * become burdensome. To avoid this overhead, the cache + * allows entries to be "pinned". A pinned entry is similar to a * protected entry, in the sense that it cannot be evicted, and that * the entry can be modified at any time. * @@ -4072,29 +3667,15 @@ typedef struct H5C_tag_info_t { * The cache must have a replacement policy, and the fields supporting this * policy must be accessible from this structure. * - * 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 (least recently used) policy - * for the first cut. - * - * To further simplify matters, I have simply included the fields needed - * by the modified LRU in this structure. When and if we add support for - * other policies, it will probably be easiest to just add the necessary - * fields to this structure as well -- we only create one instance of this - * structure per file, so the overhead is not excessive. - * - * * Fields supporting the modified LRU policy: * - * See most any OS text for a discussion of the LRU replacement policy. - * * 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 + * To deal with this issue, the usual LRU policy has been modified by adding * clean and dirty LRU lists to the usual LRU list. In general, these - * lists are only exist in parallel builds. + * lists only exist in parallel builds. * * The clean LRU list is simply the regular LRU list with all dirty cache * entries removed. @@ -4191,7 +3772,7 @@ typedef struct H5C_tag_info_t { * While the default cache size is adequate for most cases, we can run into * cases where the default is too small. Ideally, we will let the user * adjust the cache size as required. However, this is not possible in all - * cases. Thus I have added automatic cache size adjustment code. + * cases, so the cache has automatic cache size adjustment code. * * The configuration for the automatic cache size adjustment is stored in * the structure described below: @@ -4222,10 +3803,9 @@ typedef struct H5C_tag_info_t { * * resize_enabled: This is another convenience flag which is set whenever * a new set of values for resize_ctl are provided. Very - * simply, + * simply: * - * resize_enabled = size_increase_possible || - * size_decrease_possible; + * resize_enabled = size_increase_possible || size_decrease_possible; * * cache_full: Boolean flag used to keep track of whether the cache is * full, so we can refrain from increasing the size of a @@ -4248,11 +3828,6 @@ typedef struct H5C_tag_info_t { * and to prevent the infinite recursion that would otherwise * occur. * - * Note that this issue is not hypothetical -- this field - * was added 12/29/15 to fix a bug exposed in the testing - * of changes to the file driver info superblock extension - * management code needed to support rings. - * * msic_in_progress: As the metadata cache has become re-entrant, and as * the free space manager code has become more tightly * integrated with the metadata cache, it is possible that @@ -4265,11 +3840,6 @@ typedef struct H5C_tag_info_t { * and prevent the infinite regression that would otherwise * occur. * - * Note that this is issue is not hypothetical -- this field - * was added 2/16/17 to address this issue when it was - * exposed by modifications to test/fheap.c to cause it to - * use paged allocation. - * * resize_ctl: Instance of H5C_auto_size_ctl_t containing configuration * data for automatic cache resizing. * @@ -4362,8 +3932,8 @@ typedef struct H5C_tag_info_t { * call to H5C_protect(). * * image_loaded: Boolean flag indicating that the metadata cache has - * loaded the metadata cache image as directed by the - * MDC cache image superblock extension message. + * loaded the metadata cache image as directed by the + * MDC cache image superblock extension message. * * delete_image: Boolean flag indicating whether the metadata cache image * superblock message should be deleted and the cache image @@ -4476,11 +4046,11 @@ typedef struct H5C_tag_info_t { * free space manager metadata. * * mdfsm_settled: Boolean flag indicating whether the meta data free space - * manager is settled -- i.e. whether the correct space has - * been allocated for it in the file. + * manager is settled -- i.e. whether the correct space has + * been allocated for it in the file. * - * Note that the name of this field is deceptive. In the - * multi file case, the flag applies only to free space + * Note that the name of this field is deceptive. In the + * multi-file case, the flag applies only to free space * managers that are involved in allocating space for free * space managers. * @@ -4699,16 +4269,16 @@ typedef struct H5C_tag_info_t { * close, this field should only be set at that time. * * images_read: Integer field containing the number of cache images - * read from file. Note that reading an image is different - * from loading it -- reading the image means just that, - * while loading the image refers to decoding it and loading - * it into the metadata cache. + * read from file. Note that reading an image is different + * from loading it -- reading the image means just that, + * while loading the image refers to decoding it and loading + * it into the metadata cache. * - * In the serial case, image_read should always equal - * images_loaded. However, in the parallel case, the - * image should only be read by process 0. All other - * processes should receive the cache image via a broadcast - * from process 0. + * In the serial case, image_read should always equal + * images_loaded. However, in the parallel case, the + * image should only be read by process 0. All other + * processes should receive the cache image via a broadcast + * from process 0. * * images_loaded: Integer field containing the number of cache images * loaded since the last time statistics were reset. @@ -4719,21 +4289,19 @@ typedef struct H5C_tag_info_t { * should only change on those events. * * last_image_size: Size of the most recently loaded metadata cache image - * loaded into the cache, or zero if no image has been - * loaded. + * loaded into the cache, or zero if no image has been loaded. * - * At present, at most one cache image can be loaded into - * the metadata cache for any given file, and this image - * will be loaded either on the first protect, or on file - * close if no entry is protected before then. + * At present, at most one cache image can be loaded into + * the metadata cache for any given file, and this image + * will be loaded either on the first protect, or on file + * close if no entry is protected before then. * * * Fields for tracking prefetched entries. Note that flushes and evictions * of prefetched entries are tracked in the flushes and evictions arrays * discussed above. * - * prefetches: Number of prefetched entries that are loaded to the - * cache. + * prefetches: Number of prefetched entries that are loaded to the cache. * * dirty_prefetches: Number of dirty prefetched entries that are loaded * into the cache. @@ -4741,9 +4309,9 @@ typedef struct H5C_tag_info_t { * prefetch_hits: Number of prefetched entries that are actually used. * * - * As entries are now capable of moving, loading, dirtying, and deleting - * other entries in their pre_serialize and serialize callbacks, it has - * been necessary to insert code to restart scans of lists so as to avoid + * Entries may move, load, dirty, and delete + * other entries in their pre_serialize and serialize callbacks, there is + * code to restart scans of lists so as to avoid * improper behavior if the next entry in the list is the target of one on * these operations. * @@ -4757,9 +4325,9 @@ typedef struct H5C_tag_info_t { * entry in the scan. * * LRU_scan_restarts: Number of times a scan of the LRU list (that contains - * calls to H5C__flush_single_entry()) has been restarted to - * avoid potential issues with change of status of the next - * entry in the scan. + * calls to H5C__flush_single_entry()) has been restarted to + * avoid potential issues with change of status of the next + * entry in the scan. * * index_scan_restarts: Number of times a scan of the index has been * restarted to avoid potential issues with load, insertion @@ -4794,14 +4362,14 @@ typedef struct H5C_tag_info_t { * flushed in the current epoch. * * max_size: Array of size_t of length H5C__MAX_NUM_TYPE_IDS + 1. The cells - * are used to record the maximum size of any single entry + * are used to record the maximum size of any single entry * with type id equal to the array index that has resided in * the cache in the current epoch. * * max_pins: Array of size_t of length H5C__MAX_NUM_TYPE_IDS + 1. The cells - * are used to record the maximum number of times that any single - * entry with type id equal to the array index that has been - * marked as pinned in the cache in the current epoch. + * are used to record the maximum number of times that any single + * entry with type id equal to the array index that has been + * marked as pinned in the cache in the current epoch. * * * Fields supporting testing: @@ -4811,9 +4379,9 @@ typedef struct H5C_tag_info_t { * the processes mpi rank. * * get_entry_ptr_from_addr_counter: Counter used to track the number of - * times the H5C_get_entry_ptr_from_addr() function has been - * called successfully. This field is only defined when - * NDEBUG is not #defined. + * times the H5C_get_entry_ptr_from_addr() function has been + * called successfully. This field is only defined when + * NDEBUG is not #defined. * ****************************************************************************/ |