On Wed, Nov 16, 2022 at 8:35 PM Simon Riggs <simon.ri...@enterprisedb.com> wrote: > > On Wed, 16 Nov 2022 at 12:47, Bharath Rupireddy > <bharath.rupireddyforpostg...@gmail.com> wrote: > > > > On Wed, Nov 16, 2022 at 2:34 PM Simon Riggs > > <simon.ri...@enterprisedb.com> wrote: > > > > > > Reposting v6 now so that patch tester doesn't think this has failed > > > when the patch on other thread gets applied. > > > > Intention of the patch, that is, to get rid of promote_trigger_file > > GUC sometime in future, looks good to me. However, the timeout change > > to 60 sec from 5 sec seems far-reaching. While it discourages the use > > of the GUC, it can impact many existing production servers that still > > rely on promote_trigger_file as it can increase the failover times > > impacting SLAs around failover. > > The purpose of 60s is to allow for power reduction, so 5s won't do.
I understand. I know it's a bit hard to measure the power savings, I'm wondering if there's any info, maybe not necessarily related to postgres, but in general how much power gets saved if a certain number of waits/polls/system calls are reduced. > promote_trigger_file is not tested and there are better ways, so > deprecating it in this release is fine. Hm, but.. > Anyone that relies on it can update their mechanisms to a supported > one with a one-line change. Realistically, anyone using it won't be on > the latest release anyway, at least for a long time, since if they use > manual methods then they are well behind the times. I may be overly pessimistic here - the change from 5 sec to 60 sec for detecting promote_trigger_file will have a direct impact on failovers I believe. After upgrading to the version with 60 sec waiting, there'll be an increase in failover times if the developers miss to see the deprecation info about promote_trigger_file. I'm not sure what's the best way to discourage using promote_trigger_file. Maybe the change from 5 sec to 60 sec is the way. I'm not really sure. -- Bharath Rupireddy PostgreSQL Contributors Team RDS Open Source Databases Amazon Web Services: https://aws.amazon.com