On Dec 2, 3:02 am, Eric Rannaud <[email protected]> wrote:
> On Tue, Dec 1, 2009 at 6:49 PM, Stephen <[email protected]> wrote:
> >> I should say that a query with 1 result takes about 30ms. 128*30 =
> >> 3840 ms. That's pretty close to what I'm seeing for 128, indicating a
> >> linear scaling in the number of entities. Which would be really bad,
> >> and unexpected.
>
> >> It's really hard to guess what's going on internally, without any
> >> visibility of the architecture.
>
> > This is a recent change. It used to be that you were charged whatever
> > api_cpu it took to run your query, as measured on the machines. Now
> > there seems to be an algorithm that generates the cost based on your
> > entities and query type, so it will be the same from query to query.
>
> > This is good because now your costs do not suddenly go up 30% because
> > Google's infrastructure is having a bad day. The incentives used to be
> > all wrong.  The change is bad because Google didn't announce it. Are
> > the api_cpu costs exactly the same as before?  If not, it is an
> > unannounced price in/decrease.
>
> >> Has anybody looked (publicly) at datastore performance depending on
> >> query size, locality, etc? If not, I might try to gather some
> >> extensive data, and write it up.
>
> > It would be nice to work out what the algorithm for api_cpu is...
>
> Note: I am *not* using api_cpu time (not available in the Java
> runtime, as far I know). I am using system wall-clock time.
> I am doing the Java equivalent of two gettimeofday() and computes the
> difference.


It should be in the logs, which are accessible via the admin console.

--

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.


Reply via email to