We recently upgraded our Dell T110 server to a Dell T710 with a 100GB SSD drive. We were hoping that we would see a tremendous improvement in mysql select performance, but unfortunately the new system is slower than the old.
I have tried tweaking the fstab and the mysql onfiguration, but nothing has seemed to help. It seems that for some reason the system is unable to use the full speed of the drive or there is something else slowing it down.
According to hdparm the new SSD drive has a similar read speed and surprisingly a slower cached read speed.
When doing a random access data read test using seeker the SSD drive is much faster.
Old System: Dell T110, Single 2.4GHz Quad core processor 8GB of RAM 250 GB 7.2K SATA Drive Mysql 5.1 ext2 filesystem
Timing buffered disk reads: 100 MB in 0.87 seconds = 114.99 MB/sec Timing cached reads: 22636 MB in 1.99 seconds = 11361.70 MB/sec Results: 81 seeks/second, 12.28 ms random access time
New System Dell T710, Dual 2.13GHz Quad core processor 16 GB of RAM 100 GB SSD Drive Percona 5.5 ext4 filesystem
Timing buffered disk reads: 366 MB in 3.01 seconds = 121.47 MB/sec Timing cached reads: 10960 MB in 2.00 seconds = 5487.23 MB/sec Results: 3742 seeks/second, 0.27 ms random access time
The new system has the following /etc/fstab entry: /dev/mapper/vg_katahdin-lv_root / ext4 defaults,noatime,discard,data=ordered,errors=remount-ro 1 1