Paul Graydon wrote:
> I've got an identically configured test server in our dev environment.  
> I've hit the sites on it every which way but actual transactional and 
> yet to replicate the problem!  It would be awesome if we had a whole 
> series of scripted tests for our sites (over 60 different webapps), but 
> we don't yet, and I certainly haven't got the time to be able to write 
> such for now, they're not simple applications.  Wish I could narrow down 
> the range of apps it might be in!
> 
> Atom Powers wrote:
> > Can you build another, identical, server and move applications around
> > until you find the one that's troublesome?
> >
> > We have a similar problem with apache, only it actually crashes our
> > servers. We went through the same process you describe below but we
> > wenen't able to pin it down until we were able to swap applications
> > around on many (virtual) servers.
> >
> > Paul Graydon wrote:
> >> Hi all,
> >>
> >> Putting some feelers out for ideas.  I've got apache running using
> >> reverse proxy as a load balancer for over 60 different web applications
> >> on various servers.  Every now and then it'll have a thread that starts
> >> to spin, seeming to just frantically do nothing, but Apache keeps on
> >> working hosting content successfully.  It happens under both MPM Worker
> >> and Prefork, and only on the front server, never one of the applications
> >> behind it.
> >>
> >> Isolating the problem is slowly beginning to drive me crazy :)  Stracing
> >> the process doesn't show anything happening at all.  Nothing obvious is
> >> happening in the logs.  I tried adding a seconds count for responses to
> >> see whether anything was routinely slow around the time or leading up to
> >> it that might provide hints, to no avail, and tried logging the PID, but
> >> again no joy.  As I understand it Apache doesn't log until the response
> >> has been sent successfully so that's probably not all that surprising.
> >>
> >> About the only other thing I can think to do at the moment is enable
> >> mod_forensics and get it to log requests on receipt as well as at the
> >> end and look for in requests without a matching out.
> >>
> >> Anyone have any suggestions on how else I might track down what is
> >> causing this?

A great resource for Apache debugging:
http://prefetch.net/presentations/Apache_Presentation.pdf

Another great resource:
http://www.samag.com/articles/2007/0707/

-- 
Charles Polisher

_______________________________________________
Tech mailing list
[email protected]
https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech
This list provided by the League of Professional System Administrators
 http://lopsa.org/

Reply via email to