Hi Martin, A bug was opened against the Ubuntu kernel[0]. After a kernel bisect, it was found that reverting the following commit resolved this bug: commit 66c28f97120e8a621afd5aa7a31c4b85c547d33d Author: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Date: Thu Jun 6 22:15:55 2013 -0400 [SCSI] sd: Update WRITE SAME heuristics The regression was introduced as of v3.11-rc1, but it also made it's way into the stable trees. I see that you are the author of this patch, so I wanted to run this by you. I was thinking of requesting a revert for v3.12, but I wanted to get your feedback first. Thanks, Joe [0] http://pad.lv/1237392 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html