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Each node in the target cluster may be accepting work from multiple source cluster nodes from any number of source clusters and any number of feeds. Additionally, the source cluster may have a larger number of nodes than the target cluster. To prevent target cluster nodes from being overloaded, each node in the target cluster does two things. First, it delegates replication work to other nodes in the target cluster as a way method of load balancing the load. Second, each node limits the number of replications that can be done simultaneously, regardless of source. Swarm's defaults assume a moderate client load.
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