what is hyperthreading?

[krazieaznboi]

wat is hyperthreading and how to i enable/disable it? does hyperthreading increase performance?

 

[Amd2800]

Hyperthreading give ur pc another thread only 100mhz so not much

 

[krazieaznboi]

is this only for intel or AMD too?

 

[Amd2800]

Not sure .. think its intel

 

[peterhuang913]

Hyperthreading give ur pc another thread only 100mhz so not much

100MHz? LMAO1!
Lets get this straight:
Hyperthreading or Hyperthreading Technology (HTT) is an "implement" by Intel for some of their line of Pentium 4's, thus giving the name Pentium 4 w/HT. There is a similar implement on AMD's side of the bargain, ironically name Hyper Transport (HT).

Hyperthreading is just a technology to give a processor two "tasking layers". This should not be confused with two cores. HT helps the computer run faster because the computer can run two thread at the same time, not just one thread. Now what is a thread? A thread is a set of instructions that a program uses to run itself.

Normally, programs have to "wait in line" to be executed. The waiting is too slow to see sometimes. HT allows two people to go through the line at the same time. Dual core processors are like having two lines with one or two people going through at the same time.

Now to real-world performance. CPUs with HT only execute programs faster if that program can run support HT, which means the program is multi-threaded. Other programs that are single threaded will not see as much of a change in speed, although there is some increase.

 

[krazieaznboi]

On CPUZ it says my opteron has 1 core and 1 thread so does that mean I have HT enabled?

 

[peterhuang913]

It should, post a CPU-z screenie

 

[Brinson]

I have a HT cpu and STILL don't know how effective it is...anyone have a 3ghz p4 with no HT that we can benchmark against each other to see?

 

[uzi9mm]

i will give you the whole "hyper threading" thing in plain terms.

2 lanes of traffic (1 traffic cop) only 1 lane can go at a time (any given time)

Windows sends two "lanes of data or "traffic" out onto the highway. The processing point or "merging area" is managed by a hyper threading or the "police officer" he says stop to 1 lane of traffic and go to the other, he can stop and go the traffic lanes at ANY GIVEN TIME. BUT ONLY 1 LANE AT A TIME...



Now you may be wondering "this sound cool and all but it does not sound like a MAJOR performance increasing feature......"

Well you are right, on an average benchmarking matrix of non-ht vs. ht setups, sometimes the HT setup would be 2-4% maybe 5-6% faster than non-ht setups. But hey, any extra performance jumps or increases are welcomed! Back when HT when being marketed intel claimed up to 30% performance increases..... Those numbers were VERY OS and SOFTWARE dependant and rare to even come close to. Also in some areas of computing, HT would sometimes deal a blow to maximum computer efficiency and optimization.

And as peter mentioned above, to REALLY see the 5% increase (if you could notice it at all) would be in SMP (symmetrical multi-processing) programs.

 

[krazieaznboi]

okay, now do anyone know how to enable and disable HT?