Added file-based SHM segment option in SHM module and CacheAllocator. This is first half of the changes needed to enable multi-tiering in CacheLib. The multi-tiering config APIs are in a separate PR (https://github.com/facebook/CacheLib/pull/138). These config APIs are needed to enable multi-tiering. Once that PR is merged, the second half of the multi-tier changes can be upstreamed via a separate PR.
Added file-based SHM segment option in SHM module and CacheAllocator. This is first half of the changes needed to enable multi-tiering in CacheLib. The multi-tiering config APIs are in a separate PR (https://github.com/facebook/CacheLib/pull/138). These config APIs are needed to enable multi-tiering. Once that PR is merged, the second half of the multi-tier changes can be upstreamed via a separate PR.
This change is