Web Service Crashing

Hi, first let me apologize if this is not the correct forum for this question. I
didn't see a specific Web Service one. If there is a better place for my
question please let me know.

We have a web service that is used to monitor changes on a database. If it
notices a change it updates a file and lets a Windows Application running on
clients that it needs to go update itself. It's very small and fairly simple but
it dies every day. There are no errors in the server logs, or the logging that
we have implemented to track this. The really strange thing is that when this
happens the only way to fix it is to reboot the web server. Restarting IIS
doesn't help, and the web server won't render any pages until it is rebooted. We
have it isolated on it's own web server now so we can figure this one out.

I'm looking for some suggestions on how to track this bug down. The web service
is hit every few seconds by several hundred users, and it seems to break after
about 20 hours or so. 

Thank you in advance,

David

It might be worth looking at memory useage of the service over time to see if
there are any memory leaks - maybe connections or data readers not being closed
or something. If up=to-the-second information is not required you may also find
it useful to implement caching which would mean the response would be cached for
a specified period of time (5 seconds for example) which would, by the sound of
it, decrease the load by a lot without having a large impact on the
functionality.

What type of server is the web service running on? If Windows Server 2003, put
the web service into its own application pool and get the pool to recycle at say
06:00, 18:00 and 24:00. Whilst this will not fix the problem, it will limit its
severity.

Have you checked the Application and System event logs.

Run FXCOP on the web service - look in particular for any warnings about missing
Dispose calls.

Thanks for the quick response guys.  I've moved the web service to it's own app
pool and setup the recycle times.  I'm downloading FX Cop now.  I'll let you
know what I found out and post it here just in case anyone else has this type of
issue.

Stay tuned...

 David