Hannu Krosing <hannu@xxxxxxxxxxxxxxx> wrote: > This seems to indicate about 1 ms for moving pages over > user/system boundary. (Intel Core2 Duo T7500 @ 2.20GHz, Ubuntu > 9.10, 4GB RAM) Using Greg's test script on a box with two cores like this: Intel(R) Pentium(R) D CPU 3.40GHz Linux kgrittn-desktop 2.6.31-22-generic #60-Ubuntu SMP Thu May 27 00:22:23 UTC 2010 i686 GNU/Linux Dividing the run time by accumulated buffers_backend, it comes to less than 0.2 ms per dirty buffer flushed. If I get a few spare ticks I'll try again while checking what vmstat and oprofile say about how much of that went to things besides the transfer from shared buffers to the OS. I mean, it's possible I was waiting on actual disk I/O at some point. -Kevin -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
