>From: Tsunakawa, Takayuki >>From: Ideriha, Takeshi [mailto:ideriha.take...@jp.fujitsu.com] >> number of tables | 100 |1000 |10000 >> ----------------------------------------------------------- >> TPS (master) |10966 |10654 |9099 >> TPS (patch) | 11137 (+1%) |10710 (+0%) |772 (-91%) >> >> It seems that before cache exceeding the limit (no pruning at 100 and >> 1000), the results are almost same with master but after exceeding the >> limit (at >> 10000) >> the decline happens. > >How many concurrent clients? One client (default setting).
>Can you show the perf's call graph sampling profiles of both the unpatched and >patched version, to confirm that the bottleneck is around catcache eviction >and refill? I checked it with perf record -avg and perf report. The following shows top 20 symbols during benchmark including kernel space. The main difference between master (unpatched) and patched one seems that patched one consumes cpu catcache-evict-and-refill functions including SearchCatCacheMiss(), CatalogCacheCreateEntry(), CatCacheCleanupOldEntries(). So it seems to me that these functions needs further inspection to suppress the performace decline as much as possible Master(%) master |patch (%) patch 51.25% cpu_startup_entry | 51.45% cpu_startup_entry 51.13% arch_cpu_idle | 51.19% arch_cpu_idle 51.13% default_idle | 51.19% default_idle 51.13% native_safe_halt | 50.95% native_safe_halt 36.27% PostmasterMain | 46.98% PostmasterMain 36.27% main | 46.98% main 36.27% __libc_start_main | 46.98% __libc_start_main 36.07% ServerLoop | 46.93% ServerLoop 35.75% PostgresMain | 46.89% PostgresMain 26.03% exec_simple_query | 45.99% exec_simple_query 26.00% rest_init | 43.40% SearchCatCacheMiss 26.00% start_kernel | 42.80% CatalogCacheCreateEntry 26.00% x86_64_start_reservations | 42.75% CatCacheCleanupOldEntries 26.00% x86_64_start_kernel | 27.04% rest_init 25.26% start_secondary | 27.04% start_kernel 10.25% pg_plan_queries | 27.04% x86_64_start_reservations 10.17% pg_plan_query | 27.04% x86_64_start_kernel 10.16% main | 24.42% start_secondary 10.16% __libc_start_main | 22.35% pg_analyze_and_rewrite 10.03% standard_planner | 22.35% parse_analyze Regards, Takeshi Ideriha
