https://tracker.ceph.com/https://tracker.ceph.com/favicon.ico2010-11-08T22:41:57ZCeph CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=15762010-11-08T22:41:57ZSage Weilsage@newdream.net
<ul><li><strong>Estimated time</strong> set to <i>8.00 h</i></li><li><strong>Source</strong> set to <i>3</i></li></ul> CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=57292011-08-31T18:15:59ZSage Weilsage@newdream.net
<ul><li><strong>Target version</strong> set to <i>52</i></li></ul> CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=58502011-08-31T21:59:07ZSage Weilsage@newdream.net
<ul><li><strong>Target version</strong> deleted (<del><i>52</i></del>)</li><li><strong>translation missing: en.field_position</strong> deleted (<del><i>211</i></del>)</li><li><strong>translation missing: en.field_position</strong> set to <i>838</i></li></ul> CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=59922011-09-01T10:04:17ZSage Weilsage@newdream.net
<ul><li><strong>translation missing: en.field_position</strong> deleted (<del><i>849</i></del>)</li><li><strong>translation missing: en.field_position</strong> set to <i>1</i></li><li><strong>translation missing: en.field_position</strong> changed from <i>1</i> to <i>860</i></li></ul> CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=416692014-09-24T00:36:36ZLoïc Dacharyloic@dachary.org
<ul><li><strong>Project</strong> changed from <i>Ceph</i> to <i>CephFS</i></li></ul> CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=716702016-05-27T23:21:55ZGreg Farnumgfarnum@redhat.com
<ul><li><strong>Category</strong> set to <i>Correctness/Safety</i></li><li><strong>Priority</strong> changed from <i>Low</i> to <i>Normal</i></li></ul><p>I don't suppose POSIX says anything about this...</p>
<p>I think I vote for requiring a flush before renaming over existing (non-zero-sized) files.</p> CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=717622016-05-31T10:59:57ZJohn Sprayjcspray@gmail.com
<ul></ul><p>The original ticket is describing a real bug (that no longer exists), right? It's not clear to me that there's still a correctness issue in how we handle renames.</p> CephFS - Feature #83: mds: rename over old files should flush data or revert to old contents?https://tracker.ceph.com/issues/83?journal_id=718302016-05-31T21:28:54ZGreg Farnumgfarnum@redhat.com
<ul></ul><p>I think it does still exist?<br />We have an existing foo.conf, inode x<br />Write to foo.conf.tmp, inode y<br />rename foo.conf.tmp -> foo.conf<br />crash</p>
<p>We now have inode x in the stray directory, foo.conf pointing at inode y, but no RADOS objects backing up y.</p>
<p>In a local FS this isn't strictly safe either (without the syncing foo.conf.tmp first), but you're a lot more likely to be okay because most local FS implementations (either deliberately or just in practice) will flush those modifications in order. With our separate paths and writeback, we don't.</p>