QuotaCache getQuotaCache() {
    return quotaCache;
  }
Region Server Quota Manager. It is responsible to provide access to the quota information of each
user/table. The direct user of this class is the RegionServer that will get and check the
user/table quota for each operation (put, get, scan). For system tables and user/table with a
quota specified, the quota check will be a noop.
hbase-server/src/main/java/org/apache/hadoop/hbase/quotas/RegionServerRpcQuotaManager.java