The commit-interval defines how many items are processed within a single chunk. That number of items are read, processed, then written within the scope of a single transaction (skip/retry semantics not withstanding).
The page-size attribute on the paging ItemReader implementations (JdbcPagingItemReader for example) defines how many records are fetched per read of the underlying resource. So in the JDBC example, it's how many records are requested with a single hit to the DB.
While there is no direct correlation between the two attributes, it's typically considered a good idea to make them match, however they independently provide two knobs you can turn to modify the performance of your application.
With regards to your direct question, if you have the page-size set to the same as the commit-interval, then yes, I'd expect a single commit for each page.
