Re: HACKERS[PROPOSAL] split ProcArrayLock into multiple parts

Robert Haas <robertmhaas(at)gmail(dot)com> wrote on 06/07/2017 12:12:02 PM:

> > OK -- would love the feedback and any suggestions on how to mitigate
the low
> > end problems.
>
> Did you intend to attach a patch?
Yes I do -- tomorrow or Thursday -- needs a little cleaning up ...

> > Sokolov Yura has a patch which, to me, looks good for pgbench rw
> > performance. Does not do so well with hammerdb (about the same as
base) on
> > single socket and two socket.
>
> Any idea why? I think we will have to understand *why* certain things
> help in some situations and not others, not just *that* they do, in
> order to come up with a good solution to this problem.
Looking at the data now -- LWLockAquire philosophy is different -- at
first glance I would have guessed "about the same" as the base, but I can
not yet explain why we have super pgbench rw performance and "the same"
hammerdb performance.

>
> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>