What is Hyperthreading?
I've never seen this term before, but I saw it in two threads here today. Can someone please explain what it means? As simply as possible, please :)
CPU's have execution pipelines; basically an on-chip cache of instructions to execute. Often, to increase speed, CPU's will have multiple pipelines.
It's where an Intel CPU pretends to be two CPUs. (as far as the OS is concerned, one Hyperthreaded CPU is exactly like two normal CPUs).
Common Sense Guy
If you engineer highly scalable applications written to specifically to spawn 2-8 separate process/threads to use each of these processors, it's actually really useful for blocking calls and could eliminate one of the big reasons people buy dual processors.
If you have a dual cpu machine and use hyper threading you will then have 4 cpus in Windows XP. I took this question I had for our video editing guy who is selling these things. By having 4 cpus does that mean you need to buy a licence for not 1-2 cpu for the machine but for the 4 that it is seeing. As usual I got a blank stare and saw into the void that is his understanding of such things. I also asked him if Windows XP if only licensed for 1-2 cpus would use the other 2. Once again an empty stare.
My question is : you have 2 hyperthreading CPU on a dual motherboard. Will windows XP pro reports 4 CPUs because hyperthreading is on ? It does report 2 CPUs when you have 1 hyperthreading CPU. I have a 10 seats license. Am I using 1 license, 2 licenses or 4 ? What's my age ?
Windows XP and 2003 deal with hyperthreading correctly and will only count "real" processors as part of your licence rights, not the virtual ones that hyperthreading creates. You get these "for free".
A way to get you to pay for twice the number of physical processors in your server when buying enterprise software on a per processor basis. Some vendors, but not all have stopped screwing people that bad.
I think the previous poster owns a lot of AMD stock...
Go Linux Go!
"I think the previous poster owns a lot of AMD stock..." I see all the linux guys that want the cheapest possible box and don't want to pay the "intel tax" bang their heads cause mother board x, y, or z are not completely compatible with their AMD junk. I happen to think the Pentium 4's are fine and are what I'd use if I was building a personal computer.
No Mike, not the ones from Intel. The ones that are all over the web. If you are incapable of using Google, well...then nevermind. There are plenty of web sites that have done benchmarks that show the performance increase.
Go Linux Go!
I have no silly hatred of anything.
Well, you do talk about how hyperthreading is all hype, without any meaningful data to back you up. Furthermore, you brought up Itanium which is totally and completely irrelevant to this thread. So what exactly are we supposed to think?
That his hatred isn't silly?
I just thought the reference to the Itanium was relevant to prove the point that Intel blows a lot of smoke at times.
Well this doesn't help me in my decision about weather or not Hyperthreading is the way to go for my upgrade...thanks for wasting my time with useless arguements.
The way I see it is, I'm no fan of either, I'm a simple man on a machine at home for every day common use. HT doesnt have any noticable power increase for me, and it does nothing but stop my old favourite games from running (even though thats not Intel's fault)
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