Problems such as orphaned transactions and connection failures force stable queues to hold more transactions than anticipated.
If the inbound queue requires more disk space, you see a message similar to this in the Replication Server error log:
_SQM_ADD_SEGMENT: Going to wait for a segment to be
freed. Administrative action is needed.
To determine which stable queues hold the segments, log in
to the RSSD and execute:
select q_number, q_type, count(*)
from rs_segments
group by q_number, q_type
The output of this query shows the number of segments each
stable queue is using. Each segment is 1MB of disk space. Look at
the queues with the largest number of segments:
A q_type of 0 means
an outbound queue. If any outbound queues have more than
two segments, verify that the connections they service are operating.
A q_type of 1 is an
inbound queue. If any of these queues has a large number of segments,
it may contain an orphaned transaction.