You can view the number of transactions in both the inbound and outbound stable queues awaiting distribution. Replication Server reports the data in terms of segments and blocks, where one segment is equal to 1MB, and one block is equal to 16K. The data is obtained from the SQMRBacklogSeg and the SQMRBacklogBlock counters.
To view the stable queue backlog, enter:
admin stats, backlog