Does disabling Hyper-Threading increase performance?

Some trade-offs get better with time...

Since Intel introduced its Hyper-Threading technology with its Pentium 4 microprocessors back in early 2002 reviewers have occasionally noticed that under certain conditions Hyper-Threading can actually hurt performance instead of helping it. A quick summary of this issue with Hyper-Threading can be found over at Bitsum.

We decided to explore the effects of Hyper-Threading on the performance of the Ivy Bridge based Core i7-3770K by running our CPU benchmarking suite on it twice. Once with Hyper-Threading enabled, and once with Hyper-Threading disabled. As such we set-up our results table to look for applications that perform better with Hyper-Threading disabled, rather than enabled.

HT performance Does disabling Hyper Threading increase performance?

 

 

 

 

 

 

 

 

 

 

 

As you can see their are a few applications that perform marginally better, to the tune of one to two percent, with Hyper-Threading disabled. But at the same time there is far more to be gained in terms of performance from leaving Hyper-Threading enabled than there is to be gained from disabling it.

No Hyperthreading Advantage Does disabling Hyper Threading increase performance?

On average the 3770K with Hyper-Threading disabled offers only 90 percent of the performance of the same chip with this feature enabled. Thus it stands to reason that leaving Hyper-Threading enabled is the best choice for consumers.

At this point I think it’s fair to say that the days of fear mongering over performance hits due to Hyper-Threading are well past their “best if used by” dates. The implementation of this technology found in Ivy Bridge processors, and to a large extent in Sandy Bridge processors, is quite robust and well adapted to our current crop of OS schedulers. Admittedly there will continue to be workloads that are I/O bound and thus poorly suited to the methods Hyper-Threading technology, but for the most part users don’t have any reason to worry about Hyper-Threading negatively affecting application performance. As performance enhancing technologies go, Hyper-Threading is surely one of the more mature examples that Intel has to offer.S|A

Updated: Monday April 30th 10:10 AM.  Replaced image with corrected image per forum member notes.

 

zv7qrnb
The following two tabs change content below.
 Does disabling Hyper Threading increase performance?
Thomas Ryan is based in Seattle, Washington. Thomas first began to appreciate the wonders of the semiconductor industry while doing research on his previous favorite hobby, PC gaming. Having co- purchased his first computer at the ripe old age of 11, with $150 and the help of Craigslist he's been buying and building computers ever since.