ColdFusion service stops responding...

Have you checked
- ColdFusion logs (In CF Administrator - logfiles)
- Event viewer (For any CF service related entries)
- IIS or Apache (or whatever webserver you're using) log for unusual stuff

That would be the first things to investigate.

Also, ask yourself, has the issue started after a certain update? If so, review that update.

If it is a endless loop or anything related, you can have ColdFusion log long running requests. This way you can isolate the page responsible.
However, I don't think it is likely, since CF automatically restarts after 10 (=default) unresponsive requests. In your case it just stops responding.

Also, check memory usage. Maybe Jrun is at 99%, which most likely is code related.

Thanks, our DBA is in control of the reboots, and feels he needs to reboot instead of restarting services.. blah..

But I can say about the locking, I have locking on all writes, but not on reads. As from research, I've found that locking a read is not necessary. Is this incorrect, and I should include locking reads? What about excessive locking because I have a lot of application & session variables that make my application very, very dynamic. I load variables from the database into the application structure on first page hit, considered as my initialization of the app, and those variables are read throughout the app all over. Is this something I should consider changing? My only thought on that is to read them in a lock on the application page and put them in local variables instead? Is that what I'm doing ok, or do I need to go in and make this change?

This application I run is a very large reporting tool for over 8,000+ users and has a lot of pages to it, so changing this for sure won't be the easy route, but if this is what's needed, I want to be sure.

About the Logs & event viewer, I'm not really seeing much to indicate a crash... it just kills over.
As far as if it's been since an update, we started on in Oct, with the latest update... so we haven't been in Production long, but haven't done any updates since either... the latest update available from Macromedia was 10/19, and we already have it.

Thanks!

Here's what I've done since this post... Talked to a few people internally that are CF Administrators full-time. I've turned on timeout request, set it for 10 minutes, I was advised that it has to have a setting even if it's 4 hours, because a build up of requests that don't timeout can cause a hang, also made sure debuggin was completely off on production, and trusted template cache is on. Also logging slow running pages over 3 minutes, only because this is a hardcore reporting tool that has a few reports that will always be 2-3 minutes due to their size and logical processing.

Please keep the feedback coming. I appreciate it, thanks!

locking a read  IS necessary if you also write to that variable at some point.  But the lock should be of type readonly instead of exclusive.  Readonly locks do not actually take effect UNLESS an exclusive lock (a write) is in progress.

I don't really write any of the variables I'm reading in any other place... so in theory, the variables aren't being written anywhere else while they are being read.

The application variables get reset once nightly off hours. The session variables are set at login, from there, they don't change.  Should I still consider locking all my reads?

Another suggestion is to create new datasources, not database, that points to the same SQL Server db instance.  I have one db running two seperate Intranets, four public websites and an accounting system.  The Intranets use DSN1, the sites use DSN2, and the accounting app. uses DSN3.  Each connection has different settings in the cfadmin.  Since the accounting app. is all reporting (reading data) the "Allowed SQL" settings are read-only items, the "limit connections" is set to 2, "Maintain Connections" is off, and Timeout is set low.  Look at those settings to see if there is anything you could "change" also.  

If you still have problems, or have no issue with doing something "off-hours", you could set the cf service in the admin services to restart nightly, or even restart the server.  (Just another option that I have seen some people use.)

The other suggestions are very good, which I have also had to resolve in the past.
Kyle

The only reason to use locking in ColdFusion MX is to prevent race conditions. (Note that in previous versions you had to lock every read and write to a persistent scope) So I guess you can throw away a lot of locks now :) See here for more info: http://www.macromedia.com/cfusion/knowledgebase/index.cfm?id=tn_18235

And you might want to read this one: http://www.macromedia.com/cfusion/knowledgebase/index.cfm?id=tn_18772