On Tue, Oct 29, 2019 at 1:59 PM Masahiko Sawada <sawada.m...@gmail.com> wrote: > Actually after increased shared_buffer I got expected results: > > * Test1 (after increased shared_buffers) > normal : 2807 ms (hit 56295, miss 2, dirty 3, total 56300) > 2 workers : 2840 ms (hit 56295, miss 2, dirty 3, total 56300) > 1 worker : 2841 ms (hit 56295, miss 2, dirty 3, total 56300) > > I updated the patch that computes the total cost delay shared by > Dilip[1] so that it collects the number of buffer hits and so on, and > have attached it. It can be applied on top of my latest patch set[1].
I tried to repeat the test to see the IO delay with v32-0004-PoC-shared-vacuum-cost-balance.patch [1]. I tried with shared memory 4GB. I recreated the database and restarted the server before each run. But, I could not see the same I/O delay and cost is also not the same. Can you please tell me how much shared buffers did you set? Test1 (4GB shared buffers) normal: stats delay 1348.160000, hit 68952, miss 2, dirty 10063, total 79017 1 worker: stats delay 1821.255000, hit 78184, miss 2, dirty 14095, total 92281 2 workers: stats delay 2224.415000, hit 86482, miss 2, dirty 17665, total 104149 [1] https://www.postgresql.org/message-id/CAD21AoAqT17QwKJ_sWOqRxNvg66wMw1oZZzf9Rt-E-zD%2BXOh_Q%40mail.gmail.com -- Regards, Dilip Kumar EnterpriseDB: http://www.enterprisedb.com
