On Thu, Dec 17, 2015 at 4:27 AM, Fabien COELHO <coe...@cri.ensmp.fr> wrote: > > Hello Tomas, > >> I'm planning to do some thorough benchmarking of the patches proposed in >> this thread, on various types of hardware (10k SAS drives and SSDs). But is >> that actually needed? I see Andres did some testing, as he posted summary of >> the results on 11/12, but I don't see any actual results or even info about >> what benchmarks were done (pgbench?). >> >> If yes, do we only want to compare 0001-ckpt-14-andres.patch against >> master, or do we need to test one of the previous Fabien's patches? > > > My 0.02€, > > Although I disagree with some aspects of Andres patch, I'm not a committer > and I'm tired of arguing. I'm just planing to do minor changes to Andres > version to fix a potential issue if the file is closed which flushing is in > progress, but that will not change the overall shape of it. > > So testing on Andres version seems relevant to me. > > For SSD the performance impact should be limited. For disk it should be > significant if there is no big cache in front of it. There were some > concerns raised for some loads in the thread (shared memory smaller than > needed I think?), if you can include such cases that would be great. My > guess is that it should be not very beneficial in this case because the > writing is mostly done by bgwriter & worker in this case, and these are > still random.
As there are still plans to move on regarding tests (and because this patch makes a difference), this is moved to next CF. -- Michael -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers