IIRC, the loading request latency doesn't affect the average time. It's an average, I believe, and it's a moving window.
A long startup time, however, will result in the scheduler almost always favoring putting items in the pending queue instead of spinning up new instances, though. When scheduling a request, we do the lesser of: cold start time vs. sliding window of pending ms So if your app takes 10 seconds to startup and requests are spending 5 seconds in the pending queue, we will send the requests to the pending queue until the expected wait is 10+ seconds. If we decide to spin up new instances, we only spin up one instance at a time. During the spin up time, we continue to place new requests on the queue. I'm thinking we need a new section about scheduling, auto scaling and wallclock. The wallclock stuff is probably the most confusing ... Ikai Lan Developer Programs Engineer, Google App Engine Blog: http://googleappengine.blogspot.com Twitter: http://twitter.com/app_engine Reddit: http://www.reddit.com/r/appengine On Wed, Jun 8, 2011 at 1:50 PM, Jeff Schnitzer <j...@infohazard.org> wrote: > Is this documented anywhere? It's something I figured out from > occasional comments I've seen on this list over the years, but I've > never seen it mentioned in the official documentation. And it's kinda > important. > > In particular, I'd like to know what the bounds are for threaded java, > and how the average time is computed - is it mean, median, or mode? I > have a GWT app that takes one major hit at startup (possibly seconds) > and then performs lots of smaller hits as the user interacts with the > app. It would be nice to know if this will cause problems down the > road... > > Jeff > > On Tue, Jun 7, 2011 at 6:41 PM, Ikai Lan (Google) <ika...@google.com> > wrote: > > You get this error when your request waits in a pending queue. > > App Engine apps are autoscaled IF they can average under 1000ms. If they > > cannot, we do not give you additional instances, and requests line up in > a > > pending queue. If your request waits in the pending queue for more than N > > seconds (I think N is 9 at the moment but I don't know for sure off the > top > > of my head), this message is returned. > > You'll need to look at the average latency and figure out how to drop it > to > > under 1000ms. Alternatively, if you enable concurrent Java requests, > it'll > > be a higher ceiling before this error appears if you have "Always On" > since > > you can serve a total of 3 (always on instances) * M (concurrency factor, > I > > think this is 40 at the moment) requests at one time without requiring > > autoscaling. > > Ikai Lan > > Developer Programs Engineer, Google App Engine > > Blog: http://googleappengine.blogspot.com > > Twitter: http://twitter.com/app_engine > > Reddit: http://www.reddit.com/r/appengine > > > > > > On Wed, Jun 8, 2011 at 1:06 AM, holger <holger.weissbo...@gmail.com> > wrote: > >> > >> Hello everyone, > >> > >> > >> i am running a java REST service in the appengine and get this: > >> > >> "Request was aborted after waiting too long to attempt to service your > >> request. This may happen sporadically when the App Engine serving > cluster is > >> under unexpectedly high or uneven load. If you see this message > frequently, > >> please contact the App Engine team." > >> > >> > >> I see this message frequently and customer requests fail because of it. > >> Can anyone help me please! Thanks a lot. > >> > >> -- > >> You received this message because you are subscribed to the Google > Groups > >> "Google App Engine for Java" group. > >> To view this discussion on the web visit > >> > https://groups.google.com/d/msg/google-appengine-java/-/X3E4cnhhblA3Z3dK. > >> To post to this group, send email to > >> google-appengine-java@googlegroups.com. > >> To unsubscribe from this group, send email to > >> google-appengine-java+unsubscr...@googlegroups.com. > >> For more options, visit this group at > >> http://groups.google.com/group/google-appengine-java?hl=en. > > > > -- > > 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 > google-appengine-java@googlegroups.com. > > To unsubscribe from this group, send email to > > google-appengine-java+unsubscr...@googlegroups.com. > > For more options, visit this group at > > http://groups.google.com/group/google-appengine-java?hl=en. > > > > -- > 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 > google-appengine-java@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. 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