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Re: 20050420: LDM scour issue and computer lock-up

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  • Subject: Re: 20050420: LDM scour issue and computer lock-up
  • Date: Wed, 20 Apr 2005 10:38:28 -0600
Gabe,

>Date: Wed, 20 Apr 2005 12:13:24 -0400 (EDT)
>From: Gabe Langbauer <address@hidden>
>Organization: Ohio State University
>To: Steve Emmerson <address@hidden>
>Subject: Re: 20050420: LDM scour issue and computer lock-up
>Keywords: 200504191903.j3JJ3u4n010376

The above message contained the following:

> Any indication of why this crash occurs?

The LDM logfile generally won't indicate why a computer crashes.  That
information should (hopefully) be in the system logfile.  I don't know
the pathname of the system logfile under RedHat enterprise linux v. 3.
You might look in the directory /var/log.

> > When a computer crashes, I recommend deleting and recreating the
> > product-queue ("ldmadmin delqueue && ldmadmin mkqueue -f").  Otherwise,
> > the product-queue might be corrupt and you'll never know until something
> > inexplicable happens.
> Everytime this crash occurs, I've issued this command (not including the
> '-f'). However the crashes continue to occur (about once a week)

That must be frustrating.

It's highly unlikely that the LDM is causing the operating-system to
crash (if it could, then that would indicate that the operating-system
has a bug because no non-privileged process should be able to do 
that -- and the LDM process is normally a non-privileged).

> >     dayOffsetName=scour_$$
> >     cd /tmp
> >     if find . \! -name . -prune -mtime 0 -name $dayOffsetName \
> >                 | grep $dayOffsetName >/dev/null; then
> >         echo DAY_OFFSET=1
> >     elif find . \! -name . -prune -mtime 1 -name $dayOffsetName \
> >                 | grep $dayOffsetName >/dev/null; then
> >         echo DAY_OFFSET=0
> >     else
> >         echo "Couldn't discover meaning of '-mtime' argument of find(1)"
> >         exit 1
> >     fi
> The output is as follows:
> Usage: grep [OPTION]... PATTERN [FILE]...
> Try `grep --help' for more information.

What?!  That shouldn't have happened because the above syntax is perfectly
legitimate.

We need to discover why it failed.  What does the following do?

    dayOffsetName=scour_test
    cd /tmp
    if find . \! -name . -prune -mtime 0 -name $dayOffsetName | grep 
$dayOffsetName >/dev/null; then
        echo DAY_OFFSET=1
    elif find . \! -name . -prune -mtime 1 -name $dayOffsetName | grep 
$dayOffsetName >/dev/null; then
        echo DAY_OFFSET=0
    else
        echo "Couldn't discover meaning of '-mtime' argument of find(1)"
        exit 1
    fi

If the above also fails, then try playing around with the syntax to
discover the problem.

Regards,
Steve Emmerson