3 ms·
The stuff he quoted seems to make a strong case that the behaviour they implement was the intended behaviour prior to Skylake, why else specifically call it out
by _wmd 8y ago
The stuff he quoted seems to make a strong case that the behaviour they implement was the intended behaviour prior to Skylake, why else specifically call it out in the newer manuals?
Would be interested to know why you think the code was always broken. Perhaps Intel define a preferred algorithm they failed to implement?
- ptero 8y agoNot the parent, but I do not see that Intel is wrong here. New architecture makes new choices and, according to the redlined doc, they expect 1-2% performance improvements on threaded apps, which is a measurable improvement. They also explicitly call for possible degradation cases so folks who care can adjust. .NET apparently hits such a degradation case, but parent says this is due to .NET implementing spin loops in a way (almost) no one else does. If so, in this particular case Intel is doing the greatest good for the greatest number, which is reasonable. My 2c.
- arcticbull 8y agoAnd of course it's really easy for .Net to fix it for everyone in one simple patch, which it looks like they already have. I'm with you on this one.