> I've tested the performance of 8.0.1 at my dual-boot notebook
> (Linux and Windows XP).
>
> I installed 8.0.1 for Linux and Windows XP, and run pgbench
> -c 1 -t 1000 Under Linux (kernel 2.6.10) I got about 800 tps,
> and under Windows XP - about 20-24 tps.
>
> Next I switched off virtual memory under Windows (as it was
> recommended in posting
> http://www.pgsql.ru/db/mw/msg.html?mid=2026070). It does not
> help. Without virtual memory I got 15-17 tps.
Question 1: Is your writeback cache really disabled in Linux, on the
harddrive? Windows fsync will *write through the disk write cache* if
the driver is properly implemented. AFAIK, on Linux if write cache is
enabled on the drive, fsync will only get into the cache.
800tps sounds unreasonably high on a notebook.
Question 2: Please try disabling the stats connector and see if that
helps. Merlin Moncure reported some scalability issues with the stats
collector previously.
> Several yeas ago (about 1997-1998) Oleg Bartunov and me had
> the same performance results (Linux vs Windows NT + cygwin).
> It was the discussion at this list with resume that the
> reason is the implementation of shared memory under Windows.
> Every IPC operation results the HDD access.
It shouldn't in 8.0 - at least not on the native win32. Don't know about
cygwin.
//Magnus
