On 1/9/20 11:28 AM, Marc MERLIN wrote:
Howdy,
I have 6 btrfs pools on my laptop on 3 different SSDs.
After a few years, one of them is now very slow to scrub
and hands my laptop while it runs.
This started under 5.3.8, but upgrading to 5.4.8 didn't fix it.
What the hell kind of laptop are you running that has 3 different SSDs? That
thing has got to weight a ton.
Also, it output 'errors during scrubbing', but I see nothing in the kernel log:
btrfs scrub start -Bd /mnt/btrfs_pool2
scrub device /dev/mapper/pool2 (id 1) done
scrub started at Thu Jan 9 01:46:45 2020 and finished after 01:29:49
total bytes scrubbed: 1.27TiB with 0 errors
WARNING: errors detected during scrubbing, corrected
real 89m49.190s
user 0m0.000s
sys 13m26.548s
89mn is also longer than normal
Can you run the bcc tool offcputime
https://github.com/iovisor/bcc/blob/master/tools/offcputime.py
while scrub is running to get a few stack traces of where we're spending all of
our time? It'll help narrow down who is to blame. Thanks,
Josef
