I work for a company with a lot of legacy LAMP web-applications, where we are trying to refresh our hardware from ~250 physical servers to ~40 new servers w/virtualization. We have received two quotes from vendors - one is suggesting Intel processors, the other AMD.
One thing I like about the high core-counts with AMD, is that we will be able to dedicate cores to VMs, which means we have a lower chance of applications interfering with each-other due to spikes, which to a certain extent is more important to me than peak performance.
The other considerations I have in mind are:
- Power consumption may be different (not an issue in our case.)
- CPU instructions like CRC32 (SSE 4.2) will not be supported (Edit: MySQL 5.6 appears to support SSE4.2. Not sure about Apache)
- MySQL doesn't scale perfectly after ~16/~32 cores (I'm willing to accept this trade off.)
What other considerations am I missing?
(Note to moderators: I am aware of this thread - I consider the question slightly different.)
Edit: Assume that the tasks are exceptionally parallel (webservers), and that I do not care about the database servers not being so parallel.