Good catch, thanks. I'm guessing that pending_ms is the time a request stays on hold before execution? I couldn't find it documented anywhere. If so, then the question is: why would a request be in a pending state? Is it waiting for an instance to be free?
This might also be related to my other thread about the task queue not scaling up [1]. Thanks, Waleed [1] http://groups.google.com/group/google-appengine/browse_thread/thread/f8d1c6f39ad2af27/c989b852d1011cd6 On Tue, Jun 21, 2011 at 3:33 PM, Nicholas Verne <[email protected]> wrote: > One other note: > > In a large number of cases, if you the pending_ms (when it exists) to > your measurement, you come close to the ms value you circled at the > top. > > Nick Verne > > On Wed, Jun 22, 2011 at 8:18 AM, Nicholas Verne <[email protected]> wrote: > > Waleed, > > > > I'm going to have to ask one of the other infrastructure engineers > > about the log lines. The value you have circled (18386ms) is not > > always greater than the cpu_ms. I'm not sure what this value > > indicates. > > > > Nick Verne > > > > On Wed, Jun 22, 2011 at 6:27 AM, Waleed Abdulla <[email protected]> > wrote: > >> Nicholas, > >> I implemented the change you suggested (making task_t0) a global > >> variable, but that didn't change the calculations. I'm attaching another > >> screen shot. There is a big difference between the actual processing > time > >> and the time reported in the logs. It doesn't happen in all tasks, but > it's > >> often enough that it's slowing down my application considerably and > causing > >> a lot of user complaints. > >> I also calculated the total time to load the module (including time > for > >> imports). It doesn't seem to take much time (sub 1 second), and it > happens > >> only once right after I deploy a new version. So that is not an issue. > >> I've set the processing rate, bucket size, and max concurrency on > the > >> task queue to high numbers (much higher than I need). > >> Any explanation for why this is happening? > >> Waleed > >> > >> > >> > >> On Mon, Jun 20, 2011 at 6:54 PM, Brandon Wirtz <[email protected]> > wrote: > >>> > >>> Use a fetch from one thread to another. > >>> > >>> Echo Time > >>> Fetch > >>> Echo Time > >>> Do something > >>> Echo Time > >>> Echo Fetch > >>> > >>> Now you have a timeline of everything except the latency from User to > >>> Appengine. > >>> > >>> > >>> -----Original Message----- > >>> From: [email protected] > >>> [mailto:[email protected]] On Behalf Of Nicholas Verne > >>> Sent: Monday, June 20, 2011 6:03 PM > >>> To: [email protected] > >>> Subject: Re: [google-appengine] Why a big difference between execution > >>> time > >>> and response time? > >>> > >>> Yes, that's true. If you try this: > >>> > >>> task_t0 = None > >>> > >>> ... > >>> > >>> > >>> def main(argv): > >>> global task_t0 > >>> task_t0 = time.time() > >>> > >>> You'll get a measurement per request as early as we can make it. For > >>> warming > >>> requests, it might still be worth measuring the import time > >>> > >>> import time > >>> import_start = time.time() > >>> ... other imports > >>> import_duration = time.time() - import_start > >>> > >>> The import_duration global should persist and tell you how long this > >>> instance's imports took to process. Subsequent requests on that > instance > >>> don't do the imports. > >>> > >>> Nick Verne > >>> > >>> On Tue, Jun 21, 2011 at 10:49 AM, Waleed Abdulla <[email protected]> > wrote: > >>> >> A more useful measurement might be to set task_t0 as a global > >>> >> variable at the top of your file, with only the import of "time" > >>> >> preceding it > >>> > > >>> > Wouldn't that cause the 2nd, 3rd, ...nth requests to the same handler > >>> > to show wrong values? I see why setting task_t0 at the top of the > file > >>> > would apply if it was the first request that causes the handler to be > >>> > loaded. But this is happening on an ongoing basis for all requests, > >>> > not only the first for that handler. > >>> > > >>> > -- > >>> > You received this message because you are subscribed to the Google > >>> > Groups "Google App Engine" 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?hl=en. > >>> > > >>> > >>> -- > >>> You received this message because you are subscribed to the Google > Groups > >>> "Google App Engine" 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?hl=en. > >>> > >>> > >>> -- > >>> You received this message because you are subscribed to the Google > Groups > >>> "Google App Engine" 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?hl=en. > >>> > >> > >> -- > >> You received this message because you are subscribed to the Google > Groups > >> "Google App Engine" 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?hl=en. > >> > > > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine" 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?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. 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