diff options
Diffstat (limited to 'src/backend/optimizer/path/costsize.c')
| -rw-r--r-- | src/backend/optimizer/path/costsize.c | 50 |
1 files changed, 48 insertions, 2 deletions
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c index 0caac75ac5a..82c66f76caf 100644 --- a/src/backend/optimizer/path/costsize.c +++ b/src/backend/optimizer/path/costsize.c @@ -87,6 +87,7 @@ #include "optimizer/planmain.h" #include "optimizer/restrictinfo.h" #include "parser/parsetree.h" +#include "utils/guc.h" #include "utils/lsyscache.h" #include "utils/selfuncs.h" #include "utils/spccache.h" @@ -95,14 +96,13 @@ #define LOG2(x) (log(x) / 0.693147180559945) - double seq_page_cost = DEFAULT_SEQ_PAGE_COST; double random_page_cost = DEFAULT_RANDOM_PAGE_COST; double cpu_tuple_cost = DEFAULT_CPU_TUPLE_COST; double cpu_index_tuple_cost = DEFAULT_CPU_INDEX_TUPLE_COST; double cpu_operator_cost = DEFAULT_CPU_OPERATOR_COST; -int effective_cache_size = DEFAULT_EFFECTIVE_CACHE_SIZE; +int effective_cache_size = -1; Cost disable_cost = 1.0e10; @@ -456,6 +456,52 @@ cost_index(IndexPath *path, PlannerInfo *root, double loop_count) path->path.total_cost = startup_cost + run_cost; } +void +set_default_effective_cache_size(void) +{ + /* + * If the value of effective_cache_size is -1, use the preferred + * auto-tune value. + */ + if (effective_cache_size == -1) + { + char buf[32]; + + snprintf(buf, sizeof(buf), "%d", NBuffers * DEFAULT_EFFECTIVE_CACHE_SIZE_MULTI); + SetConfigOption("effective_cache_size", buf, PGC_POSTMASTER, PGC_S_OVERRIDE); + } + Assert(effective_cache_size > 0); +} + +/* + * GUC check_hook for effective_cache_size + */ +bool +check_effective_cache_size(int *newval, void **extra, GucSource source) +{ + /* + * -1 indicates a request for auto-tune. + */ + if (*newval == -1) + { + /* + * If we haven't yet changed the boot_val default of -1, just let it + * be. We'll fix it in index_pages_fetched + */ + if (effective_cache_size == -1) + return true; + + /* Otherwise, substitute the auto-tune value */ + *newval = NBuffers * DEFAULT_EFFECTIVE_CACHE_SIZE_MULTI; + } + + /* set minimum? */ + if (*newval < 1) + *newval = 1; + + return true; +} + /* * index_pages_fetched * Estimate the number of pages actually fetched after accounting for |