At 08:27 AM 4/11/2009, Andy Smith wrote:
> In what way can having more cores slow down MySQL (or any other app
>for that matter)? Are you simlpy referring to the fact that some
>mutlicore servers might be slower in single threaded preformance than
>a higher clocked single core system? If I have a mutlicore system with
>fast single threaded performance I wouldnt expect it to be slower in
>almost any cases with something like a mutliprocess database system,
There have been many blog posts claiming MySQL does not perform all
that well with multi-core processors, especially Innodb. For MyISAM the
problem is waiting for table locks, multi-processors are not going to help.
The best way to increase speed is to improve the performance of the hard
drives. The hard drives are the biggest bottleneck, not by adding more
processors. The new faster SSD's may be the answer. They have released
256gb and 512gb SSD's that are super fast and claim to have have MTBF that
is longer than most hard drives.
Here are a few of the multi-core performance blogs.
A better way to scale MySQL is to run multiple servers on Solaris.
Of course you could also try the MySQL cluster which is doing the same
thing but on multiple machines. They get around the disk problem by putting
the database in memory. So you will get a bigger bang for the buck by
distributing the load over several machines and putting the database in
memory, rather than adding multiple CPU's. Postgresql is one of the few
open sources databases that will scale effectively using multiple
processors. I wish that was the case with MySQL, but it's not.
>Quoting mos <mos99@stripped>:
>>Using more cores with MySQL doesn't mean it will run faster. In
>>fact, it could slow it down. Make sure you have done benchmarking
>>with your current computer so you can compare the difference. InnoDb
>>and MyISAM don't scale well with multi-cores I'm afraid.