Add Sieve implementation and Integrate Sieve into Cachebench

cachelib/allocator/CacheAllocator.cpp

@@ -21,4 +21,5 @@ template class CacheAllocator<LruCacheTrait>;
 template class CacheAllocator<LruCacheWithSpinBucketsTrait>;
 template class CacheAllocator<Lru2QCacheTrait>;
 template class CacheAllocator<TinyLFUCacheTrait>;
+template class CacheAllocator<SieveCacheTrait>;
 } // namespace facebook::cachelib

cachelib/allocator/CacheAllocator.h

@@ -5980,4 +5980,12 @@ using Lru2QAllocator = CacheAllocator<Lru2QCacheTrait>;
 // inserted items. And eventually it will onl admit items that are accessed
 // beyond a threshold into the warm cache.
 using TinyLFUAllocator = CacheAllocator<TinyLFUCacheTrait>;
+
+
+// CacheAllocator with Sieve eviction policy
+// It uses the access bit keep track of item's popularity
+// During eviction, the hand ptr sweeps backward to find itme with access bit turned off,
+// and turns off access bit as it goes. 
+using SieveAllocator = CacheAllocator<SieveCacheTrait>;
+
 } // namespace facebook::cachelib

cachelib/allocator/CacheTraits.h

@@ -55,5 +55,11 @@ struct TinyLFUCacheTrait {
   using AccessTypeLocks = SharedMutexBuckets;
 };
 
+struct SieveCacheTrait {
+  using MMType = MMSieve;
+  using AccessType = ChainedHashTable;
+  using AccessTypeLocks = SharedMutexBuckets;
+};
+
 } // namespace cachelib
 } // namespace facebook