While working on test_timestamp04, I saw this behaviour that if memory_page_max is set low, say 8k, the test takes really long to run. michael.cahill and I debug the issue and looks like the page is growing large, being put for force eviction, but still not getting split in memory (__wt_leaf_page_can_split keeps returning false). This happens repeatedly slowing down the test.

This ticket is to debug this issue and improve eviction/in-memory split for the scenario created in this test.