Lately my Mac Pro Late 2013 is quite laggy even in general lightweight usage. Minimising windows takes about two or three seconds, typing regularly gets delayed and takes a few seconds to catch up. The system isn't under load. Sierra, Quad Core, 64GB RAM. Done all the usual, restart, reset PRAM / SMC, Fresh install etc - none of which helped. Removed all login items. Also didn't help. Console / dmesg are replete with the following during periods of lagginess fault 13:00:51.178364 +0000 kernel void IOAccelBlockFenceMachine::block_fence_timeout(IOTimerEventSource *): prodding blockFenceInterrupt Anyone else encounter this?