BroadcasterCache and BroadcastFilter strategy - Atmosphere/atmosphere GitHub Wiki
If you are using Atmosphere 1.0.x and one of the BroadcasterCache and a BroadcastFilter like TrackMessageSizeFilter, you need to make sure the cached messages isn't the transformed one, e.g the message that was manipulated by the TrackMessageSizeFilter by adding
<init-param>
<param-name>org.atmosphere.cpr.BroadcasterCache.strategy</param-name>
<param-value>beforeFilter</param-value>
</init-param>