diff options
Diffstat (limited to 'src/H5Cprivate.h')
| -rw-r--r-- | src/H5Cprivate.h | 105 |
1 files changed, 81 insertions, 24 deletions
diff --git a/src/H5Cprivate.h b/src/H5Cprivate.h index d365755..10585a3 100644 --- a/src/H5Cprivate.h +++ b/src/H5Cprivate.h @@ -37,7 +37,7 @@ #include "H5Fprivate.h" /* File access */ -#define H5C_DO_SANITY_CHECKS 0 +#define H5C_DO_SANITY_CHECKS 1 #define H5C_DO_EXTREME_SANITY_CHECKS 0 /* This sanity checking constant was picked out of the air. Increase @@ -51,7 +51,7 @@ /* H5C_COLLECT_CACHE_STATS controls overall collection of statistics * on cache activity. In general, this #define should be set to 0. */ -#define H5C_COLLECT_CACHE_STATS 0 +#define H5C_COLLECT_CACHE_STATS 1 /* H5C_COLLECT_CACHE_ENTRY_STATS controls collection of statistics * in individual cache entries. @@ -587,7 +587,58 @@ typedef struct H5C_cache_entry_t * 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 H5C_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: + * + * H5C_flash_incr__off: Don't perform flash increases in the size of + * the cache. + * + * H5C_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 + * H5C_flash_incr__add_space section of the discussion of the + * flash_incr_mode section. This field is ignored unless flash_incr_mode + * is H5C_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 + * H5C_flash_incr__add_space. + * + * * Cache size decrease control fields: * * decr_mode: Instance of the H5C_cache_decr_mode enumerated type whose @@ -701,6 +752,8 @@ typedef struct H5C_cache_entry_t #define H5C__DEF_AR_MIN_CLEAN_FRAC 0.5 #define H5C__DEF_AR_INCREMENT 2.0 #define H5C__DEF_AR_MAX_INCREMENT ((size_t)( 2 * 1024 * 1024)) +#define H5C__DEF_AR_FLASH_MULTIPLE 1.0 +#define H5C__DEV_AR_FLASH_THRESHOLD 0.25 #define H5C__DEF_AR_DECREMENT 0.9 #define H5C__DEF_AR_MAX_DECREMENT ((size_t)( 1 * 1024 * 1024)) #define H5C__DEF_AR_EPCHS_B4_EVICT 3 @@ -713,6 +766,7 @@ enum H5C_resize_status { in_spec, increase, + flash_increase, decrease, at_max_size, at_min_size, @@ -733,45 +787,48 @@ typedef void (*H5C_auto_resize_rpt_fcn)(H5C_t * cache_ptr, typedef struct H5C_auto_size_ctl_t { /* general configuration fields: */ - int32_t version; - H5C_auto_resize_rpt_fcn rpt_fcn; + int32_t version; + H5C_auto_resize_rpt_fcn rpt_fcn; - hbool_t set_initial_size; - size_t initial_size; + hbool_t set_initial_size; + size_t initial_size; - double min_clean_fraction; + double min_clean_fraction; - size_t max_size; - size_t min_size; + size_t max_size; + size_t min_size; - int64_t epoch_length; + int64_t epoch_length; /* size increase control fields: */ - enum H5C_cache_incr_mode incr_mode; + enum H5C_cache_incr_mode incr_mode; - double lower_hr_threshold; + double lower_hr_threshold; - double increment; + double increment; - hbool_t apply_max_increment; - size_t max_increment; + hbool_t apply_max_increment; + size_t max_increment; + enum H5C_cache_flash_incr_mode flash_incr_mode; + double flash_multiple; + double flash_threshold; /* size decrease control fields: */ - enum H5C_cache_decr_mode decr_mode; + enum H5C_cache_decr_mode decr_mode; - double upper_hr_threshold; + double upper_hr_threshold; - double decrement; + double decrement; - hbool_t apply_max_decrement; - size_t max_decrement; + hbool_t apply_max_decrement; + size_t max_decrement; - int32_t epochs_before_eviction; + int32_t epochs_before_eviction; - hbool_t apply_empty_reserve; - double empty_reserve; + hbool_t apply_empty_reserve; + double empty_reserve; } H5C_auto_size_ctl_t; |