Dear community,
I'm currently running ESXi 5.5U1 on a Supermicro X9-SRL. I use a LSI 9260-8i RAID controller for all my datastores.
Main main datastore is a 4 x 3TB RAID10, consisting of WD RED series drives.
For some odd reason I can't understand, I'm experiencing 3 times faster WRITE speeds, than read speeds 
My other drives on the same controller, performs as expected.
I've tried everything to resolve this issue, without luck.
Here's what I've done:
* Recreated the array
* Tried a new firmware
* Tried latest ESXi driver(VIB)
* New SAS cables
* New controller
* New battery and cache module (BBU)
* Re-initialize the array
* Re-learn the cache and BBU
* New ESXi installation
* Removing other drives from controller
* Running a full drive check (6+hours pr. drive) on all drives, no errors detected
* Tried running disks as RAID5, this shows the same issues
All without luck.
The only way to reach slightly higher read speeds is to change the "Disk cache policy" to "No Read Ahead", but speeds are still way less then expected.
Please have a look at my attached screenshots, maybe I'm overlooking something.
Thanks
Jim
