Dear hackers, All the tests in [1] are done with autovacuum=off, so I checked how would be in autovacuum=on case.
Highlights ========== * Regression on subscriber-side became bit larger than autovacuum=on case when pgbench was run on both side * Other than that, they were mostly same. Used source =========== pgHead commit fd7d7b7191 + v46 patchset Machine details =============== Intel(R) Xeon(R) CPU E7-4890 v2 @ 2.80GHz CPU(s) :88 cores, - 503 GiB RAM 01. pgbench on publisher ======================== The workload is mostly same as [1], but autovacuum was enabled. Workload: - Ran pgbench with 40 clients for the publisher. - The duration was 300s, and the measurement was repeated 3 times. Test Scenarios & Results: - pgHead : Median TPS = 39757.24404 - pgHead + patch : Median TPS = 40871.37782 Observation: - same trend as autovacuum=off - No performance regression observed with the patch applied. - The results were consistent across runs. Detailed Results Table: - each cell shows the TPS in each case. - patch(ON) means patched and retain_conflict_info=ON is set. run# pgHEAD pgHead+patch(ON) 1 40020.19703 40871.37782 2 39650.27381 40299.31806 3 39757.24404 41017.21089 median 39757.24404 40871.37782 02. pgbench on subscriber ======================== The workload is mostly same as [1]. Workload: - Ran pgbench with 40 clients for the *subscriber*. - The duration was 300s, and the measurement was repeated 3 times. Test Scenarios & Results: - pgHead : Median TPS = 41552.27857 - pgHead + patch : Median TPS = 41677.02942 Observation: - same trend as autovacuum=off - No performance regression observed with the patch applied. - The results were consistent across runs. Detailed Results Table: run# pgHEAD pgHead+patch(ON) 1 41656.71589 41673.42577 2 41552.27857 41677.02942 3 41504.98347 42114.66964 median 41552.27857 41677.02942 03. pgbench on both sides ======================== The workload is mostly same as [1]. Workload: - Ran pgbench with 15 clients for the *both side*. - The duration was 300s, and the measurement was repeated 3 times. Test Scenarios & Results: Publisher: - pgHead : Median TPS = 17355.08998 - pgHead + patch : Median TPS = 18382.41213 Subscriber: - pgHead : Median TPS = 16998.14496 - pgHead + patch : Median TPS = 5804.129821 Observation: - Regression became larger than autovacuum = off (-50%->-60%) - No performance regression observed on the publisher with the patch applied. - The performance is reduced on the subscriber side (TPS reduction (~60%)) due to dead tuple retention for the conflict detection Detailed Results Table: On publisher: run# pgHEAD pgHead+patch(ON) 1 17537.52375 18382.41213 2 17355.08998 18408.0712 3 17286.78467 18119.77276 median 17355.08998 18382.41213 On subscriber: run# pgHEAD pgHead+patch(ON) 1 17130.63876 5886.375748 2 16998.14496 5737.799408 3 16891.2713 5804.129821 median 16998.14496 5804.129821 [1] https://www.postgresql.org/message-id/OSCPR01MB1496663AED8EEC566074DFBC9F54CA%40OSCPR01MB14966.jpnprd01.prod.outlook.com Best regards, Hayato Kuroda FUJITSU LIMITED
