Hi. When deleting a snapshot, I have observed that the disk space used by that snapshot is not immediately released (according to statvfs or df). Neither "sync" nor "btrfs filesystem sync" releases the disk space neither. The only way I have found to actually fully release the disk space is to issue the sync and then sleep until the statvfs free numbers stop changing.
This is a rather problematic approach to managing disk space. Is there any way to either force a wait until the disk space has been released? My application is automatically managing disk space in the presence of snapshots. I allow the disk (a backup) to fill up with snapshots until it is nearly full, and then to delete snapshots until I have a threshold free. However, without the disk space being released promptly and no way to wait until it is released, the loop can't tell how many snapshots to delete. -- Bruce Guenter <br...@untroubled.org> http://untroubled.org/
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