Re: two shared memory segments?

On Wednesday December 21 2005 8:24 pm, Tom Lane wrote:
> "Ed L." <pgsql(at)bluepolka(dot)net> writes:
> > I have a cluster configured for ~800MB of shared memory
> > cache (shared_buffers = 100000), but ipcs shows TWO shared
> > memory segments of ~800MB belonging to that postmaster.
> > What kind of a problem do I have here?
>
> I'd say that you had a backend crash, causing the postmaster
> to abandon the original shared memory segment and make a new
> one, but the old segment is still attached to by a couple of
> processes.

Does that make sense even if the creating pid is the same for
both?

> There was a bug awhile back whereby the stats support
> processes failed to detach from shared memory and thus would
> cause a dead shmem segment to hang around like this. What PG
> version are you running?

This is an old 7.3.7 cluster.

Ed