@Override
    public synchronized void returnGroupByStates(Map states) {
        for (State state : ((Map<String, State>) states).values()) {
            state.activeUseCount--;
        }
        partitionStateHolder.returnGroupByStates(states);
    }
State holder for  partitioned use case
modules/siddhi-core/src/main/java/io/siddhi/core/util/snapshot/state/PartitionSyncStateHolder.java