google-app-engine,asynchronous , How many Async calls we can call in one request in Google App Engine

How many Async calls we can call in one request in Google App Engine


Tag: google-app-engine,asynchronous

I'm writing an app on top of google app engine. Using Java as language.

I'm new to GAE. I want to use URL fetch service for async calls in application.

I'm having few doubts

1. How many async calls I can call in one appengine request ?

2. What happens if I call more async calls in one request, let's say 50

3. What happens these async calls takes more than 1 minute (the appengine request timeout)

4. What is default timeout for each async call (I'm assuming it is 60 sec.Is it correct)


There is no limit on the number of calls that App Engine can process in general. There are limits (quotas) set for different APIs: e.g. number of Mail API, Task API, URLFetch, etc. calls. Often quotas are different for paying customers, and in most cases you can request to increase a quota if your app requires it. In other words, these quotas do not reflect a technological limitation - they are in place to prevent abuse.

The number of requests that your app can process depends on how many instances you have running, and how fast each call can be processed. You can enable multithreading, so each instance can process multiple calls in parallel.

As for the timeouts, they depend on the instance type and the type of calls that you are making (Datastore API, Cloud Storage API, URLFetch, etc.)


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