We fail a transaction with TransactionTooLargeForCache in the following circumstances:

• The transaction is rolled back by WT due to cache pressure. This can be due to the system reaching the eviction_dirty_trigger (20% of cache) OR eviction_updates_trigger (10% of cache).
• AND the transaction's dirty pages were over 75% of pages dirty in the cache

This does not consider the case where the system reaches the update limit, not the dirty limit, and gets rolled back. As a result, we might return a WriteConflict or TemporarilyUnavailable error, which could result in a higher level retrying a transaction that will never succeed.