I've never tested the difference between CPU usage with Beast vs. JSON There are less messages to process with JSON than there are with Beast, but on the other hand all of it is string processing. I guess it depends on how busy the Beast feed is.
VRS will make use of multiple cores / processors.
You can have two instances of VRS sending feeds to each other. However if you have instance A taking a feed from a receiver, putting it into a merged feed with the feed from B and then sending that feed to B, which then merges it with its own receiver and sends it back to A, then the messages from the two receivers will ping pong back and forth between the two instances forever and things will get out of hand.
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