In a recent attempt of enabling Windows build variant in Evergreen pull request testing (post WT-4982), the build time / Makespan of a pull request test took 42m 24s. Besides the time spent waiting for task scheduling, the windows-64 build variant took longer time to run compared to other build variants. The 2 longest-running tasks were:

• unit-test-bucket01: 16m 57s (compared to 5m 57s of ubuntu1804 build variant)
• unit-test-bucket06: 14m 43s (compared to 6m 20s of ubuntu1804 build variant)

It would be great to adjust the test allocation of unit test buckets to lower the Makespan of each bucket down below 10m, for both ubuntu1804 and windows-64 build variants.