On Thursday 22 October 2009, Joe Orton wrote: > > Is the performance improvement of inode keyed locking so large > > that it is worth the hassle? If mod_dav_fs used filename keyed > > locking entirely, there would be an easy way to make file > > replacement by PUT atomic (see PR 39815). The current behaviour > > of deleting the old and the new file when the PUT fails is really > > bad. > > I believe the intent of using inode/device-number keyed locks was > to ensure that the lock database is independent of the mount > point - i.e. you could move it around in the filesystem and it'd > still work.
Interesting. Do you think this feature is actually used? > I certainly agree that the delete-on-PUT-failure behaviour is bad; > I think the correct behaviour would be to do the deletion only if > the resource is newly created by the PUT. That would still replace the old file with a broken new file. Even better would be to save the new file to a temp file and move that over the old file if it the transfer has completed successfully. But this breaks locking with inode keyed locks. Therefore I would like to move to filename keyed locks (which are already there for systems without inode numbers). Any opinions on this? Cheers, Stefan
