Hello, a little background: at Wikimedia Foundation we are running a 30-hosts Openstack Swift cluster to host user media uploads, each host has 12 spinning disks formatted individually with xfs. Some of the recently-formatted filesystems have started reporting negative usage upon hitting around 70% usage, though some filesystems on the same host kept reporting as expected: /dev/sdn1 3.7T -14T 17T - /srv/swift-storage/sdn1 /dev/sdh1 3.7T -13T 17T - /srv/swift-storage/sdh1 /dev/sdc1 3.7T 3.0T 670G 83% /srv/swift-storage/sdc1 /dev/sdk1 3.7T 3.1T 643G 83% /srv/swift-storage/sdk1 We have experienced this bug only on the last four machines to be put in service and formatted with xfsprogs 4.9.0+nmu1 from Debian Stretch. The remaining hosts were formatted in the past with xfsprogs 3.2.1 or older. We have also a standby cluster in another datacenter with similar configuration and hosts that received write traffic only but not read traffic; the standby cluster hasn't experienced the bug and all filesystems report the correct usage. As far as I can tell the difference in xfsprogs version used for formatting means defaults have changed, (e.g. crc is enabled on the affected filesystems). Have you seen this issue before and do you know how to fix it? I would love to help debugging this issue, we've been detailing the work done so far at https://phabricator.wikimedia.org/T199198 thanks in advance! Filippo -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
