On 2023-05-16 13:04, Paul Neuwirth via openSUSE Users wrote:
On Tuesday 2023-05-16 12:51, Andrei Borzenkov wrote:
On Tue, May 16, 2023 at 12:42 PM Paul Neuwirth <> wrote:
But why does "sync" (or a sysrq emergency sync) take ages then on shutdown?
Are you sure it is sync? What happens if you call the "sync" command (should wait until sync is completed) - does it take as much time? Do you see disk activity when waiting on shutdown?
sync currently finishes in less then a second, but system uptime is not quite long yet, and currently no high i/o activities, 33GiB buff/cache (at shutdown it's in the 400's). When I had those problems I ran some things like btrfs deduplication, btrfs defragmentation/compression, working on snapshots, etc. But at shutdown it's definitely the syncing. systemd/kernel/init or whoever is even trying to kill "sd_sync", I also tried sysrq emergency sync, never became the message "emergeny sync complete". last steps I see in the kernel debug output is trying to sync. ultimately it finishes and the pc is shutdown/rebooted. All the while the disk activity led of the pc is illuminated.
Is it hard disk, or ssd? I had a similar problem some time ago, with only 8 GiB IIRC. Sync took ages. I pinpointed the issue to a single partition that held my local usenet proxy server. When I migrated that partition to ssd, the issue disappeared. Also affected by it being reiserfs. -- Cheers / Saludos, Carlos E. R. (from 15.4 x86_64 at Telcontar)