Re: [boost] Re: On boost.threads

From: Beman Dawes (bdawes_at_[hidden])
Date: 2001-09-10 06:59:55

At 10:08 PM 9/9/2001, williamkempf_at_[hidden] wrote:
 >--- In boost_at_y..., flameframe_at_h... wrote:
 >> --- In boost_at_y..., williamkempf_at_h... wrote:
 >>
 >> > > I'll be interested in your research. MS people that know the
 >> > details claim
 >> > > that a critical section is incredibly optimized and should beat
 >a
 >> > mutex in
 >> > > any reasonable scenario.
 >> >
 >> > It wasn't my research.  It was research that Alexander Terekhov
 >> > (spelled from memory, sorry if I buthered it) found on the net.
 >>
 >> You could look also to detailed comparision - "Thread Performance,
 >> Critical Sections, and Mutexes" by Johnson M. Hart on
 >> http://world.std.com/~jmhart/csmutx.htm.
 >>
 >> BTW. I am agree that mutex is more _universal_ solution from a
 >> performance point of view. But to be fair - CS are faster in simple
 >> design. I believe that possibility to support them should be at
 >least
 >> taken in account.
 >
 >This was the article that someone pointed me to.  The conclusion was
 >that CS are only faster if:
 >
 >* There are less than 8 threads total in the process.
 >* You weren't running in the background.
 >* You weren't on an dual processor machine.

Note that if Intel follows through on their hyper-thread announcement, all 
performance oriented Intel processors will in effect be dual processor 
machines in two or three years.

See http://developer.intel.com/technology/hyperthread/

--Beman