On Mon, Jan 23, 2012 at 9:31 AM, Simon Riggs <si...@2ndquadrant.com> wrote: > Test duration is important for tests that don't relate to pure > contention reduction, which is every patch apart from XLogInsert.
Yes, I know. I already said that I was working on more tests to address other use cases. > I'm very happy to see that your personal work has resulted in gains > and these results are valid tests of that work, IMHO. If you only > measure throughput you're only measuring half of what users care > about. We've not yet seen any tests that confirm that other important > issues have not been made worse. I personally think throughput is awfully important, but clearly latency matters as well, and that is why *even as we speak* I am running more tests. If there are other issues with which you are concerned besides latency and throughput, please say what they are. > On particular patches.... > > * background-clean-slru-v2 related very directly to reducing the > response time spikes you showed us in your last set of results. Why > not repeat those same tests?? I'm working on it. Actually, I'm attempting to improve my previous test configuration by making some alterations per some of your previous suggestions. I plan to post the results of those tests once I have run them. > * removebufmgrfreelist-v1 related to the impact of dropping > tables/index/databases, so given the variability of the results, that > at least shows it has no effect in the general case. I think it needs some tests with a larger scale factor before drawing any general conclusions, since this test, as you mentioned above, doesn't involve much buffer eviction. As it turns out, I am working on running such tests. > That patch comes with the proviso, stated in comments: > "We didn't get the lock, but read the value anyway on the assumption > that reading this value is atomic." > So we seem to have proved that reading it without the lock isn't safe. I am not sure what's going on with that patch, but clearly something isn't working right. I don't know whether it's that or something else, but it does look like there's a bug. > The remaining patch you tested was withdrawn and not submitted to the CF. Oh. Which one was that? I thought all of these were in play. -- 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