On 25 March 2012 09:17, Simon Riggs <si...@2ndquadrant.com> wrote: > The main thing we're waiting on are the performance tests to confirm > the lack of regression.
I have extensively benchmarked the latest revision of the patch (tpc-b.sql), which I pulled from Alvaro's github account. The benchmark was of the feature branch's then-and-current HEAD, "Don't follow update chains unless caller requests it". I've had to split these numbers out into two separate reports. Incidentally, at some future point I hope that pgbench-tools can handling testing across feature branches, initdb'ing and suchlike automatically and as needed. That's something that's likely to happen sooner rather than later. The server used was kindly supplied by the University of Oregon open source lab. Server (It's virtualised, but apparently this is purely for sandboxing purposes and the virtualisation technology is rather good): IBM,8231-E2B POWER7 processor (8 cores). Fedora 16 8GB Ram Dedicated RAID1 disks. Exact configuration unknown. postgresql.conf (this information is available when you drill down into each test too, fwiw): max_connections = 200 shared_buffers = 2GB checkpoint_segments = 30 checkpoint_completion_target = 0.8 effective_cache_size = 6GB Reports: http://results_fklocks.staticloud.com/ http://results_master_for_fks.staticloud.com/ Executive summary: There is a clear regression of less than 10%. There also appears to be a new source of contention at higher client counts. I realise that the likely upshot of this, and other concerns that are generally held at this late stage is that this patch will not make it into 9.2 . For what it's worth, that comes as a big disappointment to me. I would like to thank both Alvaro and Noah for their hard work here. -- Peter Geoghegan http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training and Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
