Hi, Upon some further investigation, it seems that this is the result of the new handling of CPU intensive requests, more information about which can be found here: http://code.google.com/appengine/docs/quotas.html#Request_Limits
Specifically "Applications that are heavily cpu-bound, on the other hand, may incur some additional latency in long-running requests in order to make room for other apps sharing the same servers. " Essentially, if we observe that you have some heavily cpu-bound requests, your handler may experience additional latency. This may not always happen, and for the higher cpu request handlers, there is no way to know exactly when it may happen. -Marzia On Wed, Feb 18, 2009 at 10:21 AM, Nick Winter <livel...@gmail.com> wrote: > > We've been seeing pretty brutal response times intermittently for our > app (id: skrit), which I can't figure out. Some more info: > > * They're clustered in time: all requests will be slow for several > seconds at a time, dozens of times over a couple hours > * The long periods of slowness often happen in the morning, although > not always, and not every morning > * Traffic doesn't appear to be related, and is low (less than 5 > requests per second) > * It's not instance startup costs. I'm logging when things are > imported, and on a small request with no datastore interaction: > -- with no startup costs, normally around 30-200ms, spikes to > 1300-1600ms > -- with startup costs, normally around 1300-1600ms, spikes to > 4000-11500ms > * It doesn't seem to be related to dynamic get latency or anything > else on the serving status page. Initially, we thought it was loosely > correlated, but I think those were just flukes. This happens much more > often, and for much longer, than serving latency is ever high. > * It happens on all requests; I've just given numbers for simplest/ > most common request. > > As far as I can tell, this has only been happening for the past month > and a half or so. > > Any ideas? It's as if we're just intermittently being given really > slow serving. > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appengine@googlegroups.com To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en -~----------~----~----~----~------~----~------~--~---
