On Tue, Aug 18, 2020, 8:04 PM Stephen Frost <sfr...@snowman.net> wrote:
> Greetings, > > * Adam Sjøgren (a...@koldfront.dk) wrote: > > We have a PostgreSQL 11.3¹ running on an Ubuntu 16.04 server, which > > sometimes exhibits a behaviour I can't quite understand: simply logging > > into the database starts to take minutes to complete. > > > > We have 60 processes (workers) running on different machines accessing > > the database, that all grab jobs from a queue and update rows in a table > > after doing some calculations (which vary in time from <1s to perhaps a > > minute, many of them fast). > > > > Sometimes new database logins slow down, from usually taking <0.05s to > > taking minutes. This is for psql as a normal user using Kerberos, for > > psql as the postgres superuser, for the web-application logging into the > > database, for everything. > > When in doubt, blame DNS. > > Alternatively, in your case, the issue might be the KDC taking forever > to issue a ticket for the service. > > Note that, in both cases, this is a client-side issue. If it is a client side issue, how do you explain the behaviour that OP is not facing problem when there are only few clients? Regards, Seenu. > Once the ticket > has been acquired for the PG service, the actual authentication on the > server side should be very fast and not depend on things external > (though you might check if you have log_hostnames on..). > > Thanks, > > Stephen >
