Date: Mon, 23 Aug 1999 16:59:53 +1000 From: Stephen McKay <syssgm@detir.qld.gov.au> To: freebsd-current@freebsd.org Cc: syssgm@detir.qld.gov.au Subject: Softupdates reliability? Message-ID: <199908230659.QAA08609@nymph.detir.qld.gov.au>
next in thread | raw e-mail | index | archive | help
I had a recent crash on my home box that makes me question the reliablity
of softupdates. My home box runs 3.2-R, but as far as I can determine,
there have been no reliablity fixes to softupdates since then. So a failure
here should be relevant to -current.
Hardware: K6-2/300, 64MB ECC SDRAM, Fireport40 (ncr 875j) U/W SCSI,
2xDCAS-34330 + 1xDDRS-39130 disks (all U/W from IBM), Toshiba CD, Exabyte 8200.
This hardware has run happily for a long time, and often experiences high
load.
I was extracting from the Exabyte to the DDRS disk while applying a CTM
update from that disk against one of the DCAS disks when it crashed. The
Exabyte went wonky (took about 6 goes to get the tape ejected) and the
rest of the disk system locked up. The SCSI adapter was so confused I
had to power down.
When it recovered, there was an "UNEXPECTED SOFT UPDATE INCONSISTENCY"
which turned out to be a referenced but unallocated inode, and two zero size
directories. In all, a couple dozen files ended up in lost+found.
So, what do people think is the most likely:
1) the SCSI adapter told the disk to write crap to a couple places on the
disk (breaking an inode and some directories)
2) softupdates can't handle a sudden interruption (leaving many unwritten
blocks)
If many other people have survived sudden power loss or similar no-sync type
crashes, I'll be happy to believe option 1 caused my problem. If not, then
perhaps softupdates still has incomplete handling of dependencies. Of course,
if it is option 1, I'm keen to know what's wrong with the current driver!
Stephen.
By the way, I have a 3.2-stable machine at work on which I installed revision
1.27 of softupdates, instead of the 1.20.2.2 == 1.24 normally included. It
hasn't crashed ever :-) so I don't know if that will cause me problems. It
works fine in normal operation. Perhaps it is time to MFC.
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199908230659.QAA08609>