[hunchentoot-devel] Server sporadically hanging

[Zach Beane]

On Wed, Feb 20, 2008 at 08:09:18AM -0800, Jeff Cunningham wrote:
> I am having a problem that I can't replicate on demand but has been 
> happening with increasing frequency. I am hoping some of you might 
> suggest ways to troubleshoot it. I don't know that it is a Hunchentoot 
> problem, per se, but it may be an interaction problem between 
> Hunchentoot and Apache2 via mod_lisp2.
> 
> The symptom is the server is hung first thing in the morning when I 
> check it. The cpu is at 99% activity on the server image (sbcl). When I 
> look in the error_log I see dozens of these:
[snip]

I had trouble like this in the past, and so far in every case it was
due to me making a mistake in the handler and going into an infinite
loop. I don't know if that's the case for you, but I had good luck
debugging it by adding extra info to thread names so I could identify
handlers that might be stuck.

http://xach.livejournal.com/132391.html has a writeup.

You can also troubleshoot by interrupting all threads and requesting
their backtrace (best to write it to a file or save them to a table or
something like that). That can also help identify problems.

Zach