> Do you know which of the settings is causing lower TPS ?
> I suggest to check shared_buffers. > I'm trying to find this, but it's taking a lot of time in re-running the benchmarks changing one config setting at a time. Thanks for the tip related to shared_buffers. > > If you haven't done it, disabling THP and KSM can resolve performance > issues, > esp. with large RAM like shared_buffers, at least with older kernels. > > https://www.postgresql.org/message-id/20170718180152.GE17566%40telsasoft.com Is this a well-known performance "hack"? Is there any reason why it is not mentioned at https://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server ? Are the stability implications of fiddling with THP and KSM well-known? Also, wrt KSM, my understand was that when a process forks the process' memory is anyways "copy on write", right? What other kind of pages would end-up being de-duplicated by ksmd? (Caveat: This is the first time I'm hearing about KSM and my knowledge is based off a single reading of https://www.kernel.org/doc/html/latest/admin-guide/mm/ksm.html ) -- Saurabh.
