According to this bug report: http://bugs.centos.org/view.php?id=6548 (originally from http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=642729 ) a patch introduced in kernel 2.6.32 causes a performance drop in [certain] SSDs. This patch was later reverted in the mainline kernel. With this kernel, the reporter says, the SSD performance is now what is expected from the spec. I have built a centosplus kernel that has the referenced patch reverted. My limited test (using hdparm) did show some improvement with this kernel. kernel-ml from ELRepo (currently at 3.10.0-1.el6) gave a number similar to this plus kernel. http://people.centos.org/toracat/kernel/6/plus/bug6548/ Please test if you can and report back with your findings (good, bad, no diff ...). Note that the packages are not signed and are provided for testing purposes only. Thanks in advance for your input. Akemi / toracat