On Tue, Sep 20, 2011 at 11:01 AM, Marti Raudsepp <ma...@juffo.org> wrote: > On Fri, Sep 16, 2011 at 01:53, Simon Riggs <si...@2ndquadrant.com> wrote: >> This patch splits bgwriter into 2 processes: checkpointer and >> bgwriter, seeking to avoid contentious changes. Additional changes are >> expected in this release to build upon these changes for both new >> processes, though this patch stands on its own as both a performance >> vehicle and in some ways a refcatoring to simplify the code. > > While you're already splitting up bgwriter, could there be any benefit > to spawning a separate bgwriter process for each tablespace? > > If your database has one tablespace on a fast I/O system and another > on a slow one, the slow tablespace would also bog down background > writing for the fast tablespace. But I don't know whether that's > really a problem or not.
I doubt it. Most of the time the writes are going to be absorbed by the OS write cache anyway. I think there's probably more performance to be squeezed out of the background writer, but maybe not that exact thing, and in any case it seems like material for a separate patch. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
