Im using distributed pub/sub in an Akka.net cluster and I've begun seeing this error when pub/sub grows to approx. 1000 subscribers and 3000 publishers.
max allowed size 128000 bytes, actual size of encoded Akka.Cluster.Tools.PublishSubscribe.Internal.Delta was 325691 bytes
I don't know, but I'm guessing distributed pub/sub is trying to pass the pub/sub list to other actor systems on the cluster?
Anyway, I'm a little hesitant about boosting size limits because of this post. So what would be a reasonable approach to correcting this?
You may want to tackle with distributed pub/sub HOCON settings. Messages in Akka.Cluster.DistributePubSub are grouped together and send as deltas. You may be interested in two settings:
akka.cluster.pub-sub.max-delta-elements = 3000 says how many items can maximally consist on delta message. 3000 is the default value and you may want to lower it in order to reduce the size of the delta message (which seems to be an issue in your case).akka.cluster.pub-sub.gossip-interval = 1s indirectly affects how often gossips will be sent. The more often they're send, the smaller they may be - assuming continuously highly saturated channel.If these won't help, you may also think about reducing the size of your custom messages by introducing custom serializers with smaller payload footprint.