Re: btrfs snapshots

Am 20.03.23 um 07:38 schrieb Kees Meijs | Nefos:
> Hi there,
> 
> On 19-03-2023 18:37, Stefan G. Weichinger wrote:
>>
>> Do / did you run fileservers on btrfs? 
> 
> Yes. There's a back up server (runnning something other then AMANDA) 
> with a 40-something TB volume with btrfs. Quite often (like every other 
> month) we notice btrfs driver issues. Mostly this is a kernel oops, then 
> a reboot (watchdog) and then minutes and minutes of remounting after the 
> machine was rebooted. Then a timeout since the mount took to long, and 
> then manual intervention.

What OS / distribution is that? What type of btrfs pool ("raid level")?

> Insofar I can tell no loss yet in terms of data at rest, but obviously 
> all state and running back-ups are effected.
> 
> The oops'es seen mostly are in the context of cache or CoW related. Just 
> disabling free block cache and such, or other btrfs features, didn't 
> really help. It's noteworthy there are snapshots involved; 75 ~ 90 of them.
> 
> In general, we decided to move away from btrfs. Some systems are 
> migrated to ext4 (sometimes with LVM), some to ZFS.

Hm, I see. I am currently considering using btrfs for a new file server, 
so that is interesting to me. That box will be smaller, maybe 8 TB or 
so, running Debian 11.x (whatever is stable in a few months).

btrfs gets quite some development lately, but that is with latest 
kernels: debian stable won't come with 6.2 or something.

thanks for that information