Re: bufwait tunning

Posted in 1998

Vic Goldberg — Mon, 12 Jan 1998 13:31:16 -0500 — source: Informix-list mailing list archive (1991-1998)

Mr Cheuk Kong Lo wrote: > I'm getting quite some large bufwaits. Am I right to set a larger > RA_PAGES value to cut it down? Currently I have RA_PAGES set to 10 > and RA_THRESHOLD 8. > No, I don't think that will help. A bufwait occurs when a user is waiting for a buffer to be freed in order to allow storage of data. Obviously, the easiest fix is to increase the number of buffers, but if you already have high read/write hit rates, that may not really do the trick. You will also need to look at the number of page cleaners you have configured, as well as how dirty you're allowing the buffers to get. Also, take a look at how long your checkpoints are taking for some additional clues. Vic -- Vic Goldberg Manager, DBA Team, Cornell University (607) 254-7441 (Voice) (607) 255-6982 (Fax)