My Dell PowerEdge R630 users have reported slowdowns. Investigating did not show any issues. After a support request with Dell it was mentioned that the SSD drives I’m using are known to exhibit issues of slowdowns due to timing problems.

This has been addressed with a firmware upgrade. The drives being used are configured in a RAID10 under the PERC H730 Mini Controller

Details about the disks:

Media Type: SSD
Product ID: LITEON IT ECE-400NAS
Firmware: LPCF11XC

 

I will soon update to * Firmware Version 11XU *

Fixes and Enhancements
======================
Updated SMART attribute reportiing
Improved Interface command robustness

DST Long command handling
Improved DC cycle management

Info Found: http://www.dell.com/support/home/us/en/04/Drivers/DriversDetails?driverId=TTRG8

Release Notes: http://downloads.dell.com/FOLDER03086171M/1/Release_Notes.txt

Download:  http://downloads.dell.com/FOLDER03086139M/2/Nautilus_efi_A15_ZPE.exe

The links to the notes and download may not be valid as Dell often changes the links.  Hopefully the main page for this firmware sticks around