What is more important for a database server? Mem? Mem speed? Cores?
In my experience, what you're looking for would be in this priority order:
- Disk subsystem speed. RAID10 in my experience is best. Bonus points for SSDs.
- Total amount of RAM The more RAM, the more cache your server will be able to have.
- Memory speed. Faster RAM is obviously better than slower RAM, however RAM is always faster than disks, so more slower RAM is better than less faster RAM.
- Number of CPU cores
- CPU speed
This obviously depends on the application, but typically a database server's job is to provide really fast access to data, so the CPU speed is less important than the speed of access to the data (disks and RAM). But obviously if you're using a lot of math / calculations in your queries, you need more CPU resources.
When it comes to MySQL, you must also consider the default Storage Engine of your data.
If using MyISAM data only, you only need to consider the following
Disk speed, Memory Speed, Total RAM, CPU
Number of Cores is a big nonfactor because MyISAM (in fact, mysqld) does not utilize multiple cores.
If using InnoDB data only, now you have something to talk about when it comes to cores.
MySQL 5.5 now comes with multicore support for InnoDB.
- https://dba.stackexchange.com/a/2948/877
- https://dba.stackexchange.com/a/5670/877
- https://dba.stackexchange.com/a/5968/877
- https://dba.stackexchange.com/a/15185/877
All CPUs will be firing on all cylinders for InnoDB as long as you properly configure InnoDB do so. Believe it or not, if you do not configure InnoDB, there are instances where older versions of InnoDB will be faster out-of-the-box than newer versions.
- https://dba.stackexchange.com/a/3376/877
- https://dba.stackexchange.com/a/8385/877
- https://dba.stackexchange.com/a/16246/877
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