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(...)
Mem: 118M Active, 4155M Intact, 3110M Wired, 114M Cache, 1530M Buf, 33M Free
ARC: 843M Total, 21M MFU, 621M MRU, 19M Anon, 26M Header, 157M Other
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Running 7 instances of rsync at the moment. Seems like running several rsync instances and turning compression (-z) off speeded up...