When I try to list all pages in a space using the REST API, I send HTTP GET to: "http://localhost:8090/rest/api/content?limit=1000'". I get back 100 entries and a "next" link to the next 100 entries.
Following the links until there is no "next" in the result, Confluence returns only 300 entries from a space which contains 342 pages.

Using the JSON-RPC API returns all pages without a problem.

When I tried to repeat the queries "manually" using execution of multiple "curl" calls I got back more entries but many were duplicates.

I think this likely has something to do with restrictions and the PaginationService