This alert has been going on for days.
I've acked it
06:41:34 <jinxer-wm> (DiskSpace) firing: (6) Disk space thanos-be1001:9100:/srv/swift-storage/sdd1 5.73% free - https://wikitech.wikimedia.org/wiki/Monitoring/Disk_space - https://alerts.wikimedia.org/?q=alertname%3DDiskSpace