On 3/7/22 09:44, Gionatan Danti wrote: > Il 2022-03-07 12:09 Gaikwad, Hemant ha scritto: >> Hi, >> >> We have been looking at LVM as an option for long term backup using >> the LVM snapshots. After looking at the various forums and also >> looking at a few LVM defects, realized that LVM could be a very good >> option for short term backup, but might result in performance issues >> if the snapshots are retained for a long time. Also read we should >> restrict the number of snapshots. We are thinking of keeping it to 3, >> but do you think that could also be a performance bottleneck. A few >> forum posts also suggest memory issues with using LVM snapshots. Can >> you please help with some data on that too. Thanks in advance for >> making our decision easier. Thanks >> >> Regards, > > Classical, non-thin LVM snapshots are only meant to be short-lived (just > enough to take a backup), and the performance penalty you talk about > does apply. > Thin LVM snapshots, on the other side, command a much lower performance > penalty and can be long-lived (ie: think about a rolling snapshot > system). > So if you need multiple, long-lived snapshots, I strongly suggest you to > check lvmthin. > Regards. Also worth noting that there is a minimum time to perform an LVM operation of any type, a bit over 0.2 seconds on my machine. If you need to create snapshots exceedingly quickly, then LVM itself will be a bottleneck. Virtually all applications will not run into this problem, however. The only ones I can think of that will are container or VM managers that need to spin up a lot of containers or VMs, as Qubes OS does. The time I mentioned is the time needed to run the entire LVM command; the time I/O is suspended for is far, *far* shorter. -- Sincerely, Demi Marie Obenour (she/her/hers) Invisible Things Lab
Attachment:
OpenPGP_0xB288B55FFF9C22C1.asc
Description: OpenPGP public key
Attachment:
OpenPGP_signature
Description: OpenPGP digital signature
_______________________________________________ linux-lvm mailing list linux-lvm@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
