I have a Linux Mysql server cluster where master and slaves are overloaded by a combination of read/write i/o and by SELECT
queries load.
We purchased FusionIO cards to replace the hard drives. My question is whether to upgrade the servers themselves, or just replace the hard drives by FusionIO cards in the existing servers.
The existing servers have 266 MHz memory (Xeon E5345 - a bit outdated by now), while we can purchase servers with at least 1333 MHz RAM. We would rather not spend money on new servers, since FusionIO cards are already very costly.
We tested a FusionIO card in a brand new 1333MHz RAM server, and it gave us 4-5x speedup: but we do not know the contribution of RAM speed vs FusionIO.
What are the best practices on Linux to examine whether the RAM speed is a real bottleneck or not?