I have seen this error even for "hello world." It MAY be caused by too many simultaneous requests, but it also may be caused by a problem with appengine itself.
On Jan 22, 12:30 pm, Don Schwarz <[email protected]> wrote: > On Fri, Jan 22, 2010 at 10:55 AM, Millisecond <[email protected]> wrote: > > I'm getting this log message a lot in my application: > > > >>"Request was aborted after waiting too long to attempt to service your > > request. Most likely, this indicates that you have reached your simultaneous > > dynamic request limit. This is almost always due to excessively high latency > > in your app. Please > > seehttp://code.google.com/appengine/docs/quotas.htmlformore details." > > > I do have "excessive latency" in that I run non-trivial tasks in the > > TaskQueue handlers interacting with external systems averaging about > > 10 seconds per handler with a couple per "cycle" pushing the 30 second > > limit, but on the Dashboard my requests/second never seem to exceed > > ~1.5. I have billing enabled and my understanding is that gives me > > 500 simultaneous requests. > > That's not accurate. Where did you hear this? > > Here's the documentation we have on this: > > http://code.google.com/appengine/docs/java/runtime.htmlsays: > > *** An application can process around 30 active dynamic requests > simultaneously. This means that an application whose average server-side > request processing time is 75 milliseconds can serve up to (1000 ms/second / > 75 ms/request) * 30 = 400 requests/second without incurring any additional > latency. Applications that are heavily CPU-bound may incur some additional > latency in long-running requests in order to make room for other apps > sharing the same servers. Requests for static files are not affected by this > limit. > > *If your application is making efficient use of resources and traffic is > about to exceed your expected maximum queries per second, you can request > that the simultaneous dynamic request limit be > raised<http://code.google.com/appengine/kb/billing.html#cpu>. > App Engine can scale far beyond 30 simultaneous requests; this default limit > is in place to prevent a poorly performing or malicious app from hoarding > resources.* > > I suggest that you calculate the maximum number of simultaneous requests > that you need to serve and fill out the above form. > > Thanks, > Don -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
