[issue1298] system hang due to hammer problem?

[Matthew Dillon]

:New submission from Patrick Georgi <patrick at georgi-clan.de>:
:
:This morning, my server was unresponsive (no network traffic, no console
:response beyond switching terminals and entering ddb. Regular keypresses,
:eg. at the login prompt weren't registered).
:The last messages in the log were
:
:Feb 25 03:05:23 t-stueck kernel: HAMMER(backup): Critical error
:inode=3D24949148432 while syncing inode
:Feb 25 03:05:23 t-stueck kernel: HAMMER(backup): Forcing read-only mode
:Feb 25 03:05:29 t-stueck kernel: pid 532 (hammer), uid 0: exited on signal =
:11
:(core dumped)
:
:The HAMMER(backup) lines were also on the console.
:
:I don't have a crash dump, and the hammer coredump isn't very useful either
:(no binary with symbols around).
:The system ran a "2.3.0-development" version from ~1 week ago or so. I thin=
:k no
:hammer related changes appeared since then.
:
:The problem seems to have happened during a "hammer prune", as started by t=
:he
:nightly "hammer cleanup", as the daily run mail reported:
:
:cleanup /backup/root/home    - handle PFS #2 using /backup/pfs-snapshots/ho=
:me
:           snapshots - run
:               prune - Segmentation fault (core dumped)
:
:The security mail reported that PFS to be read-only, but it's not critical =
:(it's
:a pfs-slave to /home, on a different hammer partition than / and /home)
:
:----------
:messages: 6248
:nosy: pgeorgi
:priority: bug
:status: unread
:title: system hang due to hammer problem?

   I think the seg-fault in the utility is a different issue, and not
   the cause.  A critical error can only occur if either the I/O subsystem
   reports an error or the filesystem fills up unexpectedly.

   If your HAMMER filesystem is nowhere near full then it was probably
   an I/O error.  We can't really tell without more of the console history
   and/or a core dump.

   We'll keep an eye for other related bug reports.

   What kind of storage system is connected to the machine?  Internal
   hard drive?  SATA or PATA?  You also might as well post the dmesg
   output (post reboot), just so the information is recorded in the
   bug report.

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>