What is Google App Engine datastore size limit / how is it scalable?

Question

What is Google App Engine datastore size limit / how it is scalable?

I was read information how fast is datastore and what is API limitation but not find informaition how large could be datastore.

Answer 1

There is no limit you will ever reach (except thats of your pocket).

From google.appengine.ext.ndb key.py: Integer ids must be at least 1 and less than 2**63. These are the one you'll get automatically assigned when inserting an object.

However, this does not limit your ability to insert more objects using custom (string) keys. Its encoded form (base64) can be up to 500 bytes long, which is more than a 128 Bit Address-space, which is more than you could ever fill. (See https://blogs.oracle.com/bonwick/entry/128_bit_storage_are_you )

Answer 2

There is no physical limit. But you will reach a limit depending on the usage.

See: https://developers.google.com/appengine/docs/quotas