6 ms·
True, but you can/could easily do that with LVM snapshots and merges too. We snapshot the databases (copy on write) which is instant, then if we want to roll it
by mkhpalm 10y ago
True, but you can/could easily do that with LVM snapshots and merges too. We snapshot the databases (copy on write) which is instant, then if we want to roll it back we lvm merge and remount. Everything is pretty instant and it doesn't matter what filesystem you want to use.
- Freaky 10y agoDo LVM snapshots still cause massive performance degradation? https://www.nikhef.nl/~dennisvd/lvmcrap.html https://www.nikhef.nl/~dennisvd/lvmcrap.html
- zxcvcxz 10y agoNot for me.
- cmurf 10y agoDepends. Thick provisioned (conventional) LV snapshots take a hit. Thin provisioned LV snapshots take a much smaller hit, almost negligible.
- mkhpalm 10y agoI think its wise to have a healthy housekeeping policy if you're going to use lvm snapshots. Any point in time copy on write snapshot is going to cause performance degradation. However, it really depends on the volume and you can't speak universally for everything/everybody. For example if you have a drive with 100 files but only write to one of them. (for simplicity) The first time you rewrite those blocks are going to endure the hit for the copy on write. (dual writes) After that first rewrite of all those blocks you can't really tell the difference that the snapshot exists. This obviously assumes that you don't have a ton of additional snapshots compounding writes..