The idea behind force_evict_attempts is that we attempt to force evict before a transaction has done any work (so it's likely to succeed). It used to try just once, but at some stage there was a test/format configuration that was getting stuck because a single page was filling up the cache and this forced eviction was never succeeding. We increased the number of attempts and the test/format configuration started completing.

With the change to split busy pages in memory, we should be able to make progress in eviction now, so the number of attempts isn't critical.

You are right that this change isn't directly related to the in-memory splitting of pages. I can make it in a separate commit if you'd prefer?