On Fri, May 11, 2012 at 2:03 PM, Jeff Janes <jeff.ja...@gmail.com> wrote: > On Thu, May 10, 2012 at 10:44 AM, Bruce Momjian <br...@momjian.us> wrote: >> On Thu, May 10, 2012 at 01:11:54PM +0100, Peter Geoghegan wrote: >> >>> Why can't we call group commit group commit (and for that matter, >>> index-only scans index-only scans), so that people will understand >>> that we are now competitive with other RDBMSs in this area? "Improve >>> performance of WAL writes when multiple transactions commit at the >>> same time" seems like a pretty bad description, since it doesn't make >>> any reference to batching of commits. Also, I don't think that the >> >> I didn't call it "group commit" because we have settings we used to >> regard as group commit: > > My understanding of that patch is that is does not cause "group > commit" to happen, but rather when a group commit does happen > "naturally" it causes all members of the group to awaken more > quickly/efficiently than they previously would have.
Right. It's not a new feature; it's a performance improvement. We've had group commit for a long time; it just didn't work very well before. And it's not batching the commits better; it's reducing the lock contention around realizing that the batched commit has happened. >> I updated the release docs to call the item "group commit" because I now >> don't see any reference to that term in our docs. > > I don't think I'd mention WAL writing at all, and just say that it > improves the concurrency of locking around group commits. +1. -- 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
