Re: [PHP-DB] mySQL max connections
Hello Rasmus, Sorry to bother you, but lerdorf.com is currently down. Regards, John PS: I have been reading your new Programming PHP book. I love it! "Rasmus Lerdorf" <[EMAIL PROTECTED]> wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > I would suggest looking into MySQL's replication support. Split reads and > writes so they go to separate servers. That is, create a master server > where you send all database writes. And do all reads on the replicated > slave servers. > > Have a look at this presentation I gave last week on this stuff: > > http://pres.lerdorf.com/show/osconmysql > > The last couple of slides should be interesting to you. > > (works best with Mozilla, click on the yellow text at the top to change > slides, or use cursor-right/left) > > -Rasmus > > On Tue, 30 Jul 2002, Shane Wright wrote: > > > Hi > > > > I have a database thats taking a bit of a hammering - enough so that the > > number of connections spirals up and out of control. > > > > max_connections was originally at the default of 100 - but rising above 50 or > > so meant actual throughput dropped so the db never got a chance to keep up > > (meaning manually restarting the db). I've lowered max_connections to 40 > > which at least keeps the db alive. > > > > But, the number of connections keeps rising to and bouncing off this limit - > > and for the users that hit it a 'Too many connections' error is given. > > > > Now, I've optimised everything as much as is humanely possible - and the only > > way out I can see so far is to have some kind of connection queue to keep > > people waiting for the 1/2 second or so until the load spike drops off (I'd > > rather have a few slow pages than errors any day). > > > > Is there any way of doing this - I've looked at back_log (the listen() > > backlog), but that doesnt really apply. > > > > Short of writing a 'hide-warning-wait-a-bit-and-try-again' chunk in PHP > > (sucky!) I'm stuck! > > > > Using persistent connections doesn't stunningly help either - it only gives a > > small performance increase > > > > Any help appreciated, thanks. > > > > -- > > Shane > > http://www.shanewright.co.uk/ > > Public key: http://www.shanewright.co.uk/files/public_key.asc > > > > -- > > gpg: Warning: using insecure memory! > > gpg: Signature made Tue 30 Jul 2002 04:25:04 AM PDT using DSA key ID D08C06B4 > > gpg: Can't check signature: public key not found > > -- > > > -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DB] mySQL max connections
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Thanks for the info, looks pretty interesting - unfortunately we dont have the resources to add more servers, guess I'm just reaching capacity :( Ah well, time to start looking at alternatives, hmmm shm caches sound nice. Thanks Shane On Tuesday 30 July 2002 5:33 pm, Rasmus Lerdorf wrote: > I would suggest looking into MySQL's replication support. Split reads and > writes so they go to separate servers. That is, create a master server > where you send all database writes. And do all reads on the replicated > slave servers. > > Have a look at this presentation I gave last week on this stuff: > > http://pres.lerdorf.com/show/osconmysql > > The last couple of slides should be interesting to you. > > (works best with Mozilla, click on the yellow text at the top to change > slides, or use cursor-right/left) > > -Rasmus > > On Tue, 30 Jul 2002, Shane Wright wrote: > > Hi > > > > I have a database thats taking a bit of a hammering - enough so that the > > number of connections spirals up and out of control. > > > > max_connections was originally at the default of 100 - but rising above > > 50 or so meant actual throughput dropped so the db never got a chance to > > keep up (meaning manually restarting the db). I've lowered > > max_connections to 40 which at least keeps the db alive. > > > > But, the number of connections keeps rising to and bouncing off this > > limit - and for the users that hit it a 'Too many connections' error is > > given. > > > > Now, I've optimised everything as much as is humanely possible - and the > > only way out I can see so far is to have some kind of connection queue to > > keep people waiting for the 1/2 second or so until the load spike drops > > off (I'd rather have a few slow pages than errors any day). > > > > Is there any way of doing this - I've looked at back_log (the listen() > > backlog), but that doesnt really apply. > > > > Short of writing a 'hide-warning-wait-a-bit-and-try-again' chunk in PHP > > (sucky!) I'm stuck! > > > > Using persistent connections doesn't stunningly help either - it only > > gives a small performance increase > > > > Any help appreciated, thanks. > > > > -- > > Shane > > http://www.shanewright.co.uk/ > > Public key: http://www.shanewright.co.uk/files/public_key.asc > > > > -- > > gpg: Warning: using insecure memory! > > gpg: Signature made Tue 30 Jul 2002 04:25:04 AM PDT using DSA key ID > > D08C06B4 gpg: Can't check signature: public key not found > > -- - -- Shane http://www.shanewright.co.uk/ Public key: http://www.shanewright.co.uk/files/public_key.asc -BEGIN PGP SIGNATURE- Version: GnuPG v1.0.7 (GNU/Linux) iD8DBQE9RxKK5DXg6dCMBrQRAkSSAKCIwrEaKLg0KceZIWKdy4F5BTa3WACg1WFL 8HziL4IvBo/y+oe/zsGi7Fo= =dhdx -END PGP SIGNATURE- -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DB] mySQL max connections
I would suggest looking into MySQL's replication support. Split reads and writes so they go to separate servers. That is, create a master server where you send all database writes. And do all reads on the replicated slave servers. Have a look at this presentation I gave last week on this stuff: http://pres.lerdorf.com/show/osconmysql The last couple of slides should be interesting to you. (works best with Mozilla, click on the yellow text at the top to change slides, or use cursor-right/left) -Rasmus On Tue, 30 Jul 2002, Shane Wright wrote: > Hi > > I have a database thats taking a bit of a hammering - enough so that the > number of connections spirals up and out of control. > > max_connections was originally at the default of 100 - but rising above 50 or > so meant actual throughput dropped so the db never got a chance to keep up > (meaning manually restarting the db). I've lowered max_connections to 40 > which at least keeps the db alive. > > But, the number of connections keeps rising to and bouncing off this limit - > and for the users that hit it a 'Too many connections' error is given. > > Now, I've optimised everything as much as is humanely possible - and the only > way out I can see so far is to have some kind of connection queue to keep > people waiting for the 1/2 second or so until the load spike drops off (I'd > rather have a few slow pages than errors any day). > > Is there any way of doing this - I've looked at back_log (the listen() > backlog), but that doesnt really apply. > > Short of writing a 'hide-warning-wait-a-bit-and-try-again' chunk in PHP > (sucky!) I'm stuck! > > Using persistent connections doesn't stunningly help either - it only gives a > small performance increase > > Any help appreciated, thanks. > > -- > Shane > http://www.shanewright.co.uk/ > Public key: http://www.shanewright.co.uk/files/public_key.asc > > -- > gpg: Warning: using insecure memory! > gpg: Signature made Tue 30 Jul 2002 04:25:04 AM PDT using DSA key ID D08C06B4 > gpg: Can't check signature: public key not found > -- > -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
