On Wed, Mar 07, 2007 at 05:22:38AM +0300, Oleg Derevenetz wrote:

Sometimes (once a week approximately) I have a problem with the same
symptoms described here on SMP FreeBSD 6.2-STABLE with dual AMD Opteron(tm)
Processor 850:

http://www.freebsd.org/cgi/query-pr.cgi?pr=104406&cat=

Sometimes (apparently when CPU load suddenly goes up) all processes that
interacts with disk gets stuck in "ufs" state, but in my case
SIGSTOP/SIGCONT seemingly does not help.

See developer handbook, Deadlock Debugging chapter for instruction what
information shall be gathered to debug the problem.

OK, I built kernel with debug options and will wait for stuck. By the way, when debug options turned on, I see this message on every boot when nullfs mounting in progress:

acquiring duplicate lock of same type: "vnode interlock"
1st vnode interlock @ /usr/src/sys/kern/vfs_vnops.c:806
2nd vnode interlock @ /usr/src/sys/kern/vfs_subr.c:2040
KDB: stack backtrace:
kdb_backtrace(3,cfc60300,c05926d0,c05926d0,c05542c4,...) at kdb_backtrace+0x29
witness_checkorder(cfd5c4dc,9,c051cf1e,7f8) at witness_checkorder+0x578
_mtx_lock_flags(cfd5c4dc,0,c051cf1e,7f8,cfb28b90,...) at _mtx_lock_flags+0x78
vrefcnt(cfd5c414) at vrefcnt+0x20
null_checkvp(cff5eae0,c050c4a6,215) at null_checkvp+0x56
null_lock(f02f1a68) at null_lock+0x66
VOP_LOCK_APV(c054d540,f02f1a68) at VOP_LOCK_APV+0x87
vn_lock(cff5eae0,1002,cfc60300,cff5eae0,cff5ed04,...) at vn_lock+0xac
nullfs_root(cff76b90,2,f02f1ae0,cfc60300,0,8,0,c05cfca0,0,c051c79c,407) at 
nullfs_root+0x26
vfs_domount(cfc60300,cfe3d340,cfe3d130,d,cfe3d3f0,c05817e0,0,c051c79c,2bf) at 
vfs_domount+0x975
vfs_donmount(cfc60300,d,cfe73080,cfe73080,0,...) at vfs_donmount+0x3f9
nmount(cfc60300,f02f1d04) at nmount+0x8b
syscall(3b,3b,3b,bf7fe5f5,bf7feea0,...) at syscall+0x25b
Xint0x80_syscall() at Xint0x80_syscall+0x1f
--- syscall (378, FreeBSD ELF32, nmount), eip = 0x280bc0e7, esp = 0xbf7fe5bc, 
ebp = 0xbf7fee38 ---

This host have nullfs filesystems. Is this can be related to deadlock ?

--
Oleg Derevenetz <[EMAIL PROTECTED]> OOD3-RIPE
Phone: +7 4732 539880
Fax:   +7 4732 531415         http://www.vsi.ru
CenterTelecom Voronezh ISP    http://isp.vsi.ru

_______________________________________________
freebsd-stable@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-stable
To unsubscribe, send any mail to "[EMAIL PROTECTED]"

Reply via email to