significant memory consuming during cluster migration

[BorysTheDev]

given:

two migration processes from one node with a replica to another 2 nodes the size of the data 2GB migration for all slots before migration source node memory consumption is 2.2GB problem: during migration memory consumption sometimes increases up to 3.6 GB (not every time, also have seen 2.8GB and 2.4GB). Without replication, the maximum memory consumption for this scenario I've seen is 2.8GB.

We must investigate why we have such memory consumption during migration and reduce it. Reproducibility rate 50%. #3939 reproduce the problem