From: Corin Hartland-Swann Date: March 24 1999 6:51pm Subject: Re: RAM and caching List-Archive: http://lists.mysql.com/mysql/920 Message-Id: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Hi there, On Tue, 23 Mar 1999, matthew mcglynn wrote: > I'd like to be able to cache much or most of this in RAM > to speed queries, as this server just keeps getting busier. > My question is this: what is the algorithm for determining > how much RAM is necessary to slurp this db into memory ? > What I'm thinking is that there may be some unknown factors > that make this answer more complicated than "you need just > under a gig of RAM". > > For example, are the disk files compressed in any way? Or, > are the RAM copies compressed ? If multiple mysqld threads > open a table, does it occupy more memory than if only a single > thread opens the table ? > > The host OS is Linux 2.0.36. Right now we're using > v. 3.22.12-beta, although we'll be upgrading to whatever > the current binary release is in a few days. Somewhat off-topic, but you will have difficulty using a whole 1G of RAM with Linux 2.0.x - something to do with reserved bits of RAM. There are various issues covered in one of the HOWTO's (regarding memory). Linux 2.2.x handles up to a bit less than 2G though, iirc. Regards, Corin /---------------------------------------------\ | | | Corin Hartland-Swann - Webmaster | | | +---------------------------------------------+ | | | The International Lyrics Network | | | | http://www.lyrics.net/ | | | | mysql 3.22.20 - apache 1.3.4 - perl 5.00505 | | | \---------------------------------------------/