Test mongodb cluster performance with ycsb:

mongodb version: 3.4.0 or 3.4.16;

mongodb sharded cluster : 3 shardSver;

ycsb version:  0.12.0;

system : centos7;  memory: 48G; CPU: 24 core;

Operation sequence： 

  1. start sharded cluster;

  2. sh.enableSharding('ycsb');

  3. sh.shardCollection('ycsb.usertable',{_id:"hashed"});

  4. ycsb load data ( recordcount=20000,  operationcount=20000, threads=64);

  5. ycsb run scan (recordcount=20000, operationcount=20000, **scanproportion=1， threads=64),

At this time, it will occupy 7G of memory and will not be released for a long time.

 6. drop collection(ycsb.usertable),   and drop database(ycsb)

   Memory usage still has not decreased；