Date: Fri, 14 Mar 2008 04:18:54 GMT From: Greg Rivers <gcr@tharned.org> To: freebsd-gnats-submit@FreeBSD.org Subject: bin/121684: dump frequently hangs Message-ID: <200803140418.m2E4IsZi018350@www.freebsd.org> Resent-Message-ID: <200803140430.m2E4U1UF066877@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
>Number: 121684
>Category: bin
>Synopsis: dump frequently hangs
>Confidential: no
>Severity: critical
>Priority: high
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Fri Mar 14 04:30:01 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator: Greg Rivers
>Release: RELENG_7 as of March 12
>Organization:
>Environment:
FreeBSD 7.0-STABLE Wed Mar 12 14:41:38 CDT 2008 i386
>Description:
dump frequently hangs in this state:
UID PID PPID CPU PRI NI VSZ RSS MWCHAN STAT TT TIME COMMAND
0 87976 29731 0 8 0 35852 34164 wait I+ p2 0:00.51 dump 0afLC /dev/null 32 /dev/da0e (dump)
0 87985 87976 0 4 0 35852 34220 sbwait I+ p2 0:01.06 dump: /dev/da0e: pass 3: 0.99% done, finished in 0:16 at Thu Mar 13 15:42:10 2008 (dump)
0 87986 87985 0 20 0 35852 34180 pause I+ p2 0:00.91 dump 0afLC /dev/null 32 /dev/da0e (dump)
0 87987 87985 0 20 0 35852 34180 pause I+ p2 0:00.91 dump 0afLC /dev/null 32 /dev/da0e (dump)
0 87988 87985 0 20 0 35852 34180 pause I+ p2 0:00.92 dump 0afLC /dev/null 32 /dev/da0e (dump)
It appears to be a race condition, as repeated attempts to dump the same (clean) file system sometimes succeed and sometimes fail.
>How-To-Repeat:
dump a UFS2 filesystem.
>Fix:
The problem appears to be with the signal processing that schedules the dump subprocesses.
A full ktrace of a hung dump session is available at ftp://ftp.tharned.org/pub/dump-ktrace.bz2
>Release-Note:
>Audit-Trail:
>Unformatted:
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200803140418.m2E4IsZi018350>