message blocked in broker

Hi, all
There are more than 1000 messages blocked in my broker. Once the message come frequently, e.g, 20 per minutes, it’s blocked. Even it’s
restarted, the messages are still blocked there, so every time I should clear client queue to realse space. Could anyone give me some advice ?

This is usually caused by a message that the subscribing client/adapter cannot successfully use. Check to see if the subscriber is complaining about errors processing a message. What are the details of the subscriber?

On another reason could be the traffic created between broker and IS in the event when you apply filter condition in IS and not on broker in which case broker sends all the messages to IS and IS has to apply filter conditions before processing. What Errormsg you are getting?