On Sun, 11 Jun 2006 07:00:55 -0500 Ron Johnson <[EMAIL PROTECTED]> wrote:
> -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Andy Smith wrote: > > On Sat, Jun 10, 2006 at 10:14:41PM -0500, Ron Johnson wrote: > >> Nate Bargmann wrote: > [snip] > > This is a bit simplistic. Hyper-Threading (or more correctly, > > simultaneous multithreading (SMT)) is almost always a win because > > at any given time a CPU is often waiting for other stages of the > > pipeline to complete before it can progress with what it is > > being tasked to do. By having multiple threads of execution it > > can be getting on with something useful more of the time. > > > > Of course, unless the software being run is paralellizable then > > very little gains will be realised, but the execution part should > > never actually get slower. There have been bugs in the Pentium > > 4 architecture that have caused various software to run slower > > under hyperthreading, and lack of paralellism can lead to no > > discernible benefit, but the concept of SMT when done right has > > no downside from the point of view of a CPU executing > > instructions. > > Thanks for correcting me regarding the mechanics of it. > > I stand by my assertion, though, that Intel's HT slows down apps > unless they are very threaded. > It is usually the other way around, it usually slows down apps IF they are very threaded. > - -- > Ron Johnson, Jr. > Jefferson LA USA > > Is "common sense" really valid? > For example, it is "common sense" to white-power racists that > whites are superior to blacks, and that those with brown skins > are mud people. > However, that "common sense" is obviously wrong. > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.3 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org > > iD8DBQFEjAX3S9HxQb37XmcRAktzAJ9AknkW6OKzsJ1mdBCyLuH/9x5LnwCgjOVo > OL3kBvuAFIv62MlqunnrSzU= > =xBxl > -----END PGP SIGNATURE----- > > -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
