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RE: Repost: "Deferring operation" messages, slow operation?

Good day,

Thanks for your reply!

> If your slapd server has extremely poor performance - particularly if
> individual queries have a long latency with very low CPU use - I would
> suspect DNS name resolution problems. You may find that more logging
> makes it worse if the logs are set to include hostnames.

Thanks for the tip, but this isn't an issue.  DNS is OK, and individual
queries, other than the large ones, usually respond within a second.  I even
wrote a quick script to parse the log file and match up the start and end
times of queries to see how long they were taking, mostly to see if I had
missed any indexes.  The longest query is 3 seconds, but it's a large query
that returns over 1000 results.

> > Also, do these "failed" messages mean anything to anyone 
> else, or are they
> > not related?
> Not sure about the failed ber_get_next calls, but I am fairly sure the
> 'deferring' ones are benign.

If someone could confirm this, I'd be a lot happier.

Like I said, Googling for this error message returns heaps of frustrated
users trying to get a response back as to exactly what this error message
meant.  Here's the only response I was able to find (I've pasted the
relevant portion).


> > Apr 25 13:51:42 unix slapd[28196]: deferring operation
> > Apr 25 13:53:15 unix slapd[28196]: slapd shutdown: waiting
> > for 438 threads to terminate
> > Apr 25 13:53:26 unix squid[20651]: Squid Parent: child
> > process 29572 exited with status 0
> >
> > What would cause slapd to defer the operation?
> > Does it indicate a bad config, or resource shortage?
> > Restarting slapd seems to cure it for a while.
> Most likely both a bad config and a resource shortage. You didn't mention
> what hardware/software platform you're running on, or which version of
> OpenLDAP you're using. With default settings for OpenLDAP 2.1.17, 438
> would consume about 5.25GB of RAM in stack space alone. I hope for your
> that you're running on a 64-bit machine with much more memory than that.

However, there certainly doesn't appear to be any resource shortage on my
machine at all, and as I mentioned, not many threads are running.  A bad
config?  Well, it's basically a stock config with indexes I need added to
it, and I haven't even set any replication up on it.  I could post it here
if it would help.

If Howard Chu says that these messages indicate a problem, I'd be inclined
to believe him.  But, like I said, I don't see much else, other than that
the operation of the server is a bit slower than I expected.  If these error
messages are actually benevolent, an entry in the OpenLDAP FAQ sure would
help us end users a whole lot.

So far I haven't seen anything else that looks abnormal.

Anything else that I could try?  Anyone else know what these error messages
could mean?

Darren Gamble
Planner, Regional Services
Shaw Cablesystems GP
630 - 3rd Avenue SW
Calgary, Alberta, Canada
T2P 4L4
(403) 781-4948