kewl. Well, 8k request out of PG kernel might turn into an "X"Kb request at disk/OS level, but duly noted.
Did you scan the code for this, or are you pulling this recollection from the cognitive archives? :-) -----Original Message----- From: Jim C. Nasby [mailto:[EMAIL PROTECTED] Sent: Tuesday, April 19, 2005 8:12 PM To: Mohan, Ross Cc: pgsql-performance@postgresql.org Subject: Re: [PERFORM] How to improve db performance with $7K? On Mon, Apr 18, 2005 at 06:41:37PM -0000, Mohan, Ross wrote: > Don't you think "optimal stripe width" would be > a good question to research the binaries for? I'd > think that drives the answer, largely. (uh oh, pun alert) > > EG, oracle issues IO requests (this may have changed _just_ > recently) in 64KB chunks, regardless of what you ask for. > So when I did my striping (many moons ago, when the Earth > was young...) I did it in 128KB widths, and set the oracle > "multiblock read count" according. For oracle, any stripe size > under 64KB=stupid, anything much over 128K/258K=wasteful. > > I am eager to find out how PG handles all this. AFAIK PostgreSQL requests data one database page at a time (normally 8k). Of course the OS might do something different. -- Jim C. Nasby, Database Consultant [EMAIL PROTECTED] Give your computer some brain candy! www.distributed.net Team #1828 Windows: "Where do you want to go today?" Linux: "Where do you want to go tomorrow?" FreeBSD: "Are you guys coming, or what?" ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
