I am using SQL Server transactional replication, and have noticed that on a daily basis all of the publications for a distributor are being blocked when the distribution agent cleanup job executes. I have seen this block persist for up to 2 hours. Some of the subscriptions require extremely low latency, so this is a big problem for me right now.
I have read that setting the HistoryVerboseLevel to 0 will stop logging to MSdistribution_history database. Having done this, the blocking subsided for the subscriptions that i changed the distributor profiles for. However, within three days all of the subscriptions were marked inactive.
I'm out of ideas at this point, so was hoping that someone else has a solution. My next step is try enabling snapshot isolation on the distribution database, but feel that this is a "sledge hammer" approach.