What is the batch request limit for Facebooks APIs?

Question

Does anyone know what is the limit for batch requests when using FBs APIs? From their documentation:

Limit

We are currently limiting the number of packet requests to 20.

A source

This is not clear. Is it 20 for 600 seconds? In a day? In just one application?

Answer 1

This means that 20 individual requests can be combined together into one batch request, which saves you from sending 20 individual HTTP requests at the same time.

Answer 2

Now 50. 50 request / package

Answer 3

If you have more than twenty (20), you can build an array and then break them into groups of 20 or less and encode them through your PHP in one "session". We have one application that will run 600 - 700 OG requests, but this is sloooooooow, up to 300 seconds, several times, depending on the FB.