good default max page size

[J]

i've implemented paging for all services to retreive a dump of an
account structure to json in the case of catastrophe on our end. i'm
currently using a page size of 100 for all services, but it's pretty
dang slow.

what's the biggest number that i can use for a default page size?

[AdWords API Advisor]

Hi,

This number can vary per service, but is usually 10,000 I believe. It
might be more efficient to use a smaller page size though, so I
recommend you run some tests with different page sizes.

Best,
- Eric Koleda, AdWords API Team