First pass at shared memory performance counters.
First pass at shared memory performance counters.

IMCG/levelDB,basho/leveldb,IMCG/levelDB,icholy/leveldb,IMCG/levelDB,tempbottle/leveldb-1,tempbottle/leveldb-1,basho/leveldb,icholy/leveldb,tempbottle/leveldb-1,basho/leveldb,icholy/leveldb