public void addCsmOffsets(int partitionId, long offsetCfm, long tmpOffset) {
        OffsetCsmItem offsetCsmItem = partitionCsmMap.get(partitionId);
        if (offsetCsmItem == null) {
            OffsetCsmItem tmpItem = new OffsetCsmItem(partitionId);
            offsetCsmItem = partitionCsmMap.putIfAbsent(partitionId, tmpItem);
            if (offsetCsmItem == null) {
                offsetCsmItem = tmpItem;
            }
        }
        offsetCsmItem.addCsmOffsets(offsetCfm, tmpOffset);
    }
The offset snapshot of the consumer group on the partition.
inlong-tubemq/tubemq-server/src/main/java/org/apache/inlong/tubemq/server/broker/offset/OffsetCsmRecord.java