On 2011-08-20, at 4:02 PM, Tim Worman wrote: > Back in January I started this discussion on this same topic: > > http://lists.apple.com/archives/webobjects-dev/2011/Jan/msg00224.html > >>> I have an app that, during the course of normal usage, is starting httpd >>> processes on the server that instantly hit 100% CPU usage of one core. This >>> can happen multiple times during times when the app is under heavier load. >>> After some time I can have many httpd processes where TOP reports each >>> using 100% of a core. When I try to log into the app and poke around to try >>> and reproduce the issue, I am unable. > > This is an update to my original post hoping to see if there are anymore > thoughts on origin. More recently, I have been able to reproduce the issue in > my own usage of the app - something I wasn't able to do before. It seems to > be easier to generate the issue now that there are more ajax requests. The > methods executed by these requests are not intensive or long responses and > should return a result in seconds. Some symptoms: > > - When the actions are executed, busy indicators properly spin while the > browser awaits a response from the server. When the issue occurs, the > response never comes. > - while continuing to await a response there is concurrently an httpd process > that pegs he processor at 100% > - if I kill the process on the server, the browser immediately updates > properly as if the request had run properly > > It's almost as if apache is somehow receiving an ill-formed request and > chokes on it. The problem is, there are no errors in the console or anything > strange in any apache logs. Has anyone ever seen behavior like this or have > any ideas as to how I could analyze it further?
I've seen something like this. It appeared that the woadaptor (i.e. mod_webobjects) did not believe that it had received all of the response from the application. The app had nothing more to send and so the woadaptor just hung there waiting for data that would never come. I did not track down why this happened, but it did seem to be load related. My suspicion was that there is a concurrency bug in the woadaptor. Chuck -- Chuck Hill Senior Consultant / VP Development Practical WebObjects - for developers who want to increase their overall knowledge of WebObjects or who are trying to solve specific problems. http://www.global-village.net/products/practical_webobjects _______________________________________________ Do not post admin requests to the list. They will be ignored. Webobjects-dev mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/webobjects-dev/archive%40mail-archive.com This email sent to [email protected]
