John G. Heim wrote: > But I'm confused about disk. I would think disk pspeed > would be fairly important.
That entirely depends on your database usage pattern: What is your total dataset size? What is your working set (i.e. data which is commonly/regularly accessed)? Can you reasonably fit your working set into RAM? What is your read/write ratio (i.e. select vs update/insert)? If at all possible, aim to have enough RAM for your working set, if you can't then disk speed becomes important for read performance. Write latency (time taken to commit to permanent storage) is critical if you are doing a lot of writes - in this case getting a RAID controller with battery-backed cache is a win - otherwise it probably isn't. So... if you have a database (or databases) with a working set of 10G, and a high read:write ratio, then disk performance probably isn't going to be important. Another hint (excuse if you know this stuff already), but you can very readily get large performance improvements by optimising your mysql server config (e.g. using mysqlanalyze, and this munin plugin: http://github.com/kjellm/munin-mysql/downloads ) Tim. -- South East Open Source Solutions Limited Registered in England and Wales with company number 06134732. Registered Office: 2 Powell Gardens, Redhill, Surrey, RH1 1TQ VAT number: 900 6633 53 http://seoss.co.uk/ +44-(0)1273-808309 _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
