Java Reference
In-Depth Information
•
Outgoing Bandwidth (billable):
The amount of data the application
sends in response to requests. This includes responses over HTTP,
HTTPS, outbound e-mail messages, and data in outgoing requests
from the URL Fetch service.
•
Incoming Bandwidth (billable):
The amount of data received by the
application from inbound requests. This includes data over HTTP,
HTTPS, and responses from the URL Fetch service.
■
Note
Secure Outgoing Bandwidth and Secure Incoming Bandwidth both carry their own measurements.
Both of these metrics count toward the overall measurement as well.
•
CPU Time (billable)
: The measurement of the total processing time
the application is using to handle requests. This includes time
spent running the application and performing datastore operations
but excludes time spent waiting for the responses from other
services. For example, if your application is waiting for a response
from a URL Fetch request, you are not using CPU time for that
transaction.
CPU time is reported in
seconds
. This is equivalent to the number of CPU cycles that
can be performed by a 1.2 GHz Intel x86 processor in that amount of time. The actual
number of cycles may vary and depends on the conditions internal to App Engine.
The number is adjusted for reporting purposes by using the 1.2 GHz processor as a
benchmark.
If you're using Python on App Engine you can profile your application in a bit
more detail during a transaction. See the online documentation on App Engine for
more details. Hopefully, the ability to query your current quota usage statistics
will be available for Java applications soon. If you're an administrator of Java
applications you can use the Administration Console to examine the logs and see
how much CPU time has been used for each request to your application. Here are
a few key things to consider when designing your application that may help
conserve resources.
•
Writes to the datastore use approximately five times the CPU
resources as reads from the datastore.
•
More resources are needed for datastore writes that require an
update to indexes.
