dafde14e08
Remove medium size classes, because concurrent dirty page purging is no longer capable of purging inactive dirty pages inside active runs (due to recent arena/bin locking changes). Enhance tcache to support caching large objects, so that the same range of size classes is still cached, despite the removal of medium size class support.
jemalloc is a general-purpose scalable concurrent malloc(3) implementation. The INSTALL file contains information on how to configure, build, and install jemalloc.