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f60d176a5e
SearchCatCacheList and ReleaseCatCacheList. Previously, we incremented and decremented the refcounts of list member tuples along with the list itself, but that's unnecessary, and very expensive when the list is big. It's cheaper to change only the list refcount. When we are considering deleting a cache entry, we have to check not only its own refcount but its parent list's ... but it's easy to arrange the code so that this check is not made in any commonly-used paths, so the cost is really nil. The bigger gain though is to refrain from DLMoveToFront'ing each individual member tuple each time the list is referenced. To keep some semblance of fair space management, lists are just marked as used or not since the last cache cleanout search, and we do a MoveToFront pass only when about to run a cleanout. In combination, these changes reduce the costs of SearchCatCacheList and ReleaseCatCacheList from about 4.5% of pgbench runtime to under 1%, according to my gprof results. |
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| access | ||
| bootstrap | ||
| catalog | ||
| commands | ||
| executor | ||
| lib | ||
| libpq | ||
| main | ||
| nodes | ||
| optimizer | ||
| parser | ||
| po | ||
| port | ||
| postmaster | ||
| regex | ||
| rewrite | ||
| storage | ||
| tcop | ||
| utils | ||
| Makefile | ||
| nls.mk | ||