Re: Revised patch for fixing archiver shutdown behavior

Tom Lane wrote:

> There was discussion of having a lock file for the archiver, but
> it's still an open issue. I'm not sure how to solve the problem
> of stale lockfiles --- unlike the postmaster, the archiver can't
> assume that it's the only live process with the postgres userid.
> For example, after a system crash-and-restart, it's entirely
> likely that the PID formerly held by the archiver is now held
> by the bgwriter, making the lockfile (if any) look live.

Ah, right :-(

> Maybe we should go back to the plan of having the postmaster
> wait for the archiver to exit.

Yeah, that seems the safest to me -- the problem is that it complicates
the shutdown sequence a fair bit, because postmaster must act
differently depending on whether archiving is enabled or not: wait for
bgwriter exit if disabled, or for archiver exit otherwise.

--
Alvaro Herrera http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support