Comment 6 for bug 1686687

Phillip Susi (psusi) wrote :

Come to think of it, since you say it only seems to happen on a multipath SAN and not on a normal disk, it may be related to the order of requests being sent to the disk and XFS's use of io barriers to make sure that the unmap request for the old data does not hit the disk after the new filesystem metadata has been written. IIRC, xfs has mount options to control the use of io barriers. Do you have them enabled?