On Sat, 29 Feb 2020 at 06:39, Alvaro Herrera <alvhe...@2ndquadrant.com> wrote: > > On 2020-Feb-27, Peter Eisentraut wrote: > > > So this patch relaxes this a bit. Upon receipt of > > XLOG_PARAMETER_CHANGE, we still check the settings but only issue a > > warning and set a global flag if there is a problem. Then when we > > actually hit the resource issue and the flag was set, we issue another > > warning message with relevant information. Additionally, at that > > point we pause recovery, so a hot standby remains usable. > > Hmm, so what is the actual end-user behavior? As I read the code, we > first send the WARNING, then pause recovery until the user resumes > replication; at that point we raise the original error.
I think after recovery is paused users will be better to restart the server rather than resume the recovery. I agree with this idea but I'm slightly concerned that users might not realize that recovery is paused until they look at that line in server log or at pg_stat_replication because the standby server is still functional. So I think we can periodically send WARNING to inform user that we're still waiting for parameter change and restart. Regards, -- Masahiko Sawada http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
