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LWN.net Weekly Edition for May 16, 2013
A look at the PyPy 2.0 release
PostgreSQL 9.3 beta: Federated databases and more
LWN.net Weekly Edition for May 9, 2013
(Nearly) full tickless operation in 3.10
Preventing overly-optimistic spinning
Posted Aug 26, 2010 15:12 UTC (Thu) by PaulMcKenney (subscriber, #9624)
But you can always give it a try and see what happens.
Posted Aug 26, 2010 16:10 UTC (Thu) by jzbiciak (✭ supporter ✭, #5246)
In a MESI, you would end up bouncing lines (S => M transition on the first writer, S => I on the others, followed by M => S and I => S). An ESI system (write through caches w/ no notion of "modified"), you'd get something similar.
In a MOESI such as Athlon's, I believe you minimize the cost. The first writer does an S => O and broadcasts the write to everyone else that's in S.
From that, I'd say it's rather important to measure on multiple architectures, since the tradeoffs will vary.
Posted Aug 26, 2010 16:25 UTC (Thu) by PaulMcKenney (subscriber, #9624)
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