Hi, Looking for some advices about server hardware choosing I am currently using dedicated server with following hardware: cpu: dual XEON 5410 8GB RAM 3x1.5TB HDD (5200rpm) with RAID controller so in following configuration hard drives makes that server very slow specially for mysql where a lot of storage required. What would you suggest ? I am thinking to replace those 3 x 1.5TB with 1 SAS 500GB drive(15K rpm), so its not going to be very expensive. Does 1 SAS drive on 15K rpm will work faster than those 3x1.5TB joined with RAID ?
Why would you need drives of that size? Seriously, they are WAY too large for the average installation You'll never fill them up unless you are attempting to run some massive company's DB, and you'll run out of CPU power and RAM long before you ever fill them. Better spending money on smaller but faster drives and a proper hardware raid controller with battery backup (around $500 for a half-decent one) A single SAS at 15K isn't going to give you much of a boost and it become a single point of failure which is a no-no when it comes to databases. I'd get another SATA drive and run RAID 10 rather than 3x1.5TB plus 1xSAS. What we do with DB servers is run RAID1 for OS, RAID1 for DB software, and RAID10 for Databases, but if it comes down to 4 drives I'd go for RAID10 for DB's. At a push I'd go for RAID5 plus a hot-spare, but I prefer RAID10.
1 SAS drive is not a solution. RAID 10 is the way to go. Another way is to increase RAM to avoid massive disk IO. Be sure to tune database settings accordingly. Unfortunately it is very database-specific area, but for mysql there exists nice script. Just search google for tuning-primer.sh
Depending on site traffic, you probably need to tweak mysql to better use your ram, and increase your usage of indexes. If you need to upgrade your hardware, you're better off going Raid10 as someone suggested. Increase Ram if you're really short there. Hardware might double or triple your speed, but fixing up mysql could do a 100x increase.