Re: Before & After Under The Giant Lock


I just want to add my 2 cents, that my recent experience with FreeBSD MP
has been extremely positive. I tend to use highly CPU bound MP programs,
typically lots and lots of floating point operations. It used to be that
Linux beat FreeBSD hands down - now FreeBSD seems to have a slight edge!
Basically my program runs about twice as fast when I run two threads as
opposed to one - I cannot see doing any better than that!

pure computation does not need kernel operations most of the time.. ie.
multi-threading kernel wont help much ;)


Yes, I know. But something else was also done to FreeBSD, perhaps fine
tuning with the scheduler, that did bring about massive improvements.


I assume you're using ULE. Jeff has gone to great lengths to take
cache affinity into account. This may be what you are benefiting from.

-Kip
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