On Sun, 4 Oct 2020 at 18:01, Adrian Klaver <adrian.kla...@aklaver.com> wrote:
> On 10/4/20 9:54 AM, Robert Inder wrote: > > I am moving a database from PSQL 9 (!) on CentOS 6 to PSQL 12 on CentOS 7 > > It would help to know what the x in 9.x is? Before version 10 of > Postgres, the second number denoted a major version. > 9.4. Moving to 12.4. > > > > > I have a pair of servers -- one live, one standby. > > The live server defines an archive_command as "rsync...." to shift WAL > > files to the standby server, > > The standby server uses "pg_standby" to monitor and process incoming WAL > > files. > > I believe this is all very vanilla, and indeed changes made in the live > > database are duly shipped to the standby. > > > > BUT... > > > > One of the things I like about the old PGSQL 9 setup is that it > > generates and ships a WAL file every few minutes, even if nothing has > > happened in the database. > > I find it re-assuring to be able to see WAL files arriving and being > > processed without problem even when the live system was idle. > > > > But I cannot get PGSQL 12 to do this. It only writes (and thus ships) > > WAL files when something happens in the database. > > If the database is idle, it simply does not write any WAL files. > > > > I thought I would get WAL files written from an idle database if, in > > postgresql.conf, I set "archive_timeout" to 120. > > > > And I've tried setting "checkpoint_timeout" to 90s, > > > > But to no avail. No WAL files are written unless the database changes. > > > > So what am I missing? How CAN I get postgresql 12 to write > > "unnecessary" WAL files every couple of minutes? > > > > Robert. > > > > -- > > Robert Inder, 0131 229 1052 / 07808 > > 492 213 > > Interactive Information Ltd, 3, Lauriston Gardens, Edinburgh EH3 9HH > > Registered in Scotland, Company no. SC 150689 > > Interactions speak louder > > than words > > > -- > Adrian Klaver > adrian.kla...@aklaver.com > > > -- Robert Inder, 0131 229 1052 / 07808 492 213 Interactive Information Ltd, 3, Lauriston Gardens, Edinburgh EH3 9HH Registered in Scotland, Company no. SC 150689 Interactions speak louder than words