On Wed, Nov 05, 2003 at 11:30:46AM -0000, Alexis Guia wrote: > > Sorry, but I disagree :/ > I always used 250MB of key buffer, and MySQL never allocates more than > 50MB, in my database. > Read buffer is only allocated when full scans are done. > Join buffer is allocated when there are joins without index use. > Sort buffer is allocated when needed, and etc...
I'm confused. Exactly which of my statements are you disagreeing with? Jeremy > P.S.: you can test it easily, doing specific queries for each case. > > -----Original Message----- > From: Jeremy Zawodny [mailto:[EMAIL PROTECTED] > Sent: terça-feira, 4 de Novembro de 2003 23:51 > To: Alexis Guia > Cc: 'Benjamin KRIEF'; [EMAIL PROTECTED] > Subject: Re: mysql memory usage > > On Tue, Nov 04, 2003 at 10:09:01AM -0000, Alexis Guia wrote: > > > > Hi, > > > > I think that MyISAM uses the key buffer only if needed. The same > happens > > with almost all the other buffers (read buffer, sort buffer, etc.). > > True, but there's a subtle difference between "uses" and "allocates." > If you tell MySQL that it has 16GB for a key_buffer, it'll allocate > 16GB even if it only ever uses 28KB. The same is true of several > (probably all?) other buffers. > > Jeremy > -- > Jeremy D. Zawodny | Perl, Web, MySQL, Linux Magazine, Yahoo! > <[EMAIL PROTECTED]> | http://jeremy.zawodny.com/ > > MySQL 4.0.15-Yahoo-SMP: up 51 days, processed 1,925,645,484 queries > (428/sec. avg) > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > > -- Jeremy D. Zawodny | Perl, Web, MySQL, Linux Magazine, Yahoo! <[EMAIL PROTECTED]> | http://jeremy.zawodny.com/ MySQL 4.0.15-Yahoo-SMP: up 53 days, processed 1,974,835,485 queries (430/sec. avg) -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
