This allows WiredTiger to work in caches where the number of pages is small enough that an old snapshot could block itself from evicting in order to read new pages.
The test/format program randomly generates WiredTiger files with different size objects and then does operations on those files. The goal is to test the WiredTiger file formats. test/format should be compiled with a version of Berkeley DB (which it uses to verify format's results). Create a link "db" in the build_posix directory that links to the top-level of a Berkeley DB distribution directory which contains a configured and compiled build_unix subdirectory.