On Tue, Dec 6, 2016 at 11:26 PM, Michael Paquier <michael.paqu...@gmail.com> wrote: > On Wed, Dec 7, 2016 at 12:32 PM, Fujii Masao <masao.fu...@gmail.com> wrote: >> So, isn't it better to compare the performance of some algorithms and >> confirm which is the best for quorum commit? Since this code is hot, i.e., >> can be very frequently executed, I'd like to avoid waste of cycle as much >> as possible. > > It seems to me that it would be simple enough to write a script to do > that to avoid any other noise: allocate an array with N random > elements, and fetch the M-th element from it after applying a sort > method. I highly doubt that you'd see much difference with a low > number of elements, now if you scale at a thousand standbys in a > quorum set you may surely see something :*) > Anybody willing to try out?
You could do that, but first I would code up the simplest, cleanest algorithm you can think of and see if it even shows up in a 'perf' profile. Microbenchmarking is probably overkill here unless a problem is visible on macrobenchmarks. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers