On Thu, 2006-01-19 at 11:22 -0800, Mickael Maddison wrote:
Thursday, January 19, 2006, 10:14:54 AM, you wrote:
On Thu, 2006-01-19 at 09:11 -0800, Paul Heinlein wrote:
On Thu, 19 Jan 2006, Fong Vang wrote:
Did you just ended up running without hyperthreading? Did you ever find a solution? It seems an awful waste if you can't use it.
I'd have a hard time calling a performance hit of no more than 10% to 15% (and typically much less than that) an "awful waste." :-)
exactly ... hyperthreading is mostly "hype" ... and very little "rthreading" :)
I've heard a lot of criticism on hyperthreading on various lists. While I haven't actually measured the performance of a machine that has it enabled vs. disabled, I have noticed that the same machine with hyperthreading enabled responds much faster to SSH logins etc. when the machine is under heavy loads. Given that I've had no problems with using HT, I'm happy to have it.
Absolutely, if it works on given hardware then use it, any performance gain is worth having :)
But if you look objectively at the gain, it is not 2x the performance ... maybe 1.25x ... maybe a little more ... maybe not.
If it is broken, it is not the end of the world though, which I think was the initial point.
It is not nearly as much an increase in performance as you see with dual core processors, for example.