Guild Wars 2

i heard that in some case i7 cpu’s HT(hyperthreading) can make fps lower

especially in WvW situation.

is it true?

my system is

i7 2600
h77 main board
Nvidia GTX670 or ATI HD7950
4G x2 DDR3 ram
windows7 64 bit

This principle applies to nearly every game. I’ll explain how Hyperthreading works and why it is detrimental to gamers.

For every physical core your processor has, Hyperthreading adds an additional thread. This “logical” core can be utilized by programs as another core. The problem is that these logical cores are less powerful and more unreliable than the physical cores on the chip.

Your processor has 4 cores and GW2 will only really focus on a couple of those. Disable HyperThreading and let GW2 run the best it can on the physical cores inherently on your chip. You will most likely get slightly higher fps and more stability.

I wouldn’t use the word unreliable, since they’re as reliable as any other core. A nice short writeup: http://www.novell.com/coolsolutions/feature/637.html

tl;dr: Shared cache between logical cores and additional switching overhead makes it run worse when there’s anything besides a game thread scheduled onto the same physical core.

IMO leave it on, u got a 2600k, use all of it. if u didnt want/need HT then u coulda got a 2500k instead. Same goes for 3570k vs 3770k.

In theory depending on the usuage u could actually harm performance. Say ur game uses 4 threads, with HT off , the rest of ur system has no other threads to use for background tasks like general OS processes. With HT on u have another 4 threads left to run background tasks. Ofc as above, HT can also imporve performance.

I run a 3930k with 6 physical cores, more than enough for GW2 to run on without HT, but i keep HT on.. would GW2 run better with HT off ..maybe ..but the difference would likely be so small that its not worth the hassle of turning HT back on when i want to use those extra threads.

Oh if u havnt already, unpark ur core’s. it has been said to slightly increase performance in GW2 and can reduce stutter in other games.
Turning off HT sort of does this for u as u bassicaly never have parked cores as ur using them all. With HT on however ur not using them all specialy in GW2, Windows then parks them, when they get used they have to unpark which can cause stutter / drop in performance. If u simply turn of core parking u can then keep HT on.

EDIT: also btw from what i know, HT on 2nd and 3rd gen i7’s is dynamic for programs that use less than the max number of available threads. So for Gw2 that ‘mainly’ uses 3 it will use 3 physical cores 1st before using virtual ones. Bassicaly from what i know it will only use a virtual core when the physical ones r all in use. This means u r unlikely to see any significant difference outside of expected variation when testing ingame performance between HT on vs Off. The max iv ever seen my processor hit in overall usuage in GW2 is 50% and that was at a peak loading period during the wintersday event. 50% of 12 availabe threads that 6, my CPu has 6 physical cores so even then i was likely only using maybe 1 ..or 2 vitual ones if uisng 5 or 4 physical ones. It also means that if my 6 core CPU can hit 50% usuage in the those extreme examples, ur gunna want to keep HT on, on a 4 core CPU otherwise ull max out the usuage with HT off.

SolarNova.1052: the problem is, that windows is kinda dumb, and moves threads around in a dumb way, sometimes it will put 2 heavy threads on the same core(one on the physical core, one on the logical/virtual core)

this happens alot with ALL cpu’s with HT, and despite what some would try and say, no other os is any better for multi processing, they all have their flaws.(took over a decade to get any sort of meaningful multi processing/smp/smt support in linux for example)

try process lasso its a bit smarter at where it sends threads and how it manages them for you then windows built in scheduler.

but the fact is yes, HT can seriously harm the performance of some apps and games, its why many i7 owners i know who got chips with HT restart to enable or disable it when doing various tasks.

if your on AMD video, you can use Radeon Pro to set what cores gw2 is allowed to use, this can help ALOT, as far as i know theres no equivalent for nVidia users(sorry green guys)

honestly your best bet is to grab radeon pro if you got an amd videocard, use it to lock the game to 3 of 4 physical cores this will help avoid the issue with to much heavy processing being piled on one physical core.

HT is great for light tasks that dont keep the cores pipes full/busy, but its murder on perf for tasks that do….

47% perf hit when encoding audio in ogg vorbis with ht enabled for example.(using any encoder that uses all cores such as dbpoweramp)

Download “process Lasso” it is a very advanced task manager (what windows should have if wasn’t an OS made for kitten ppl), it will allow u to set up the games to use the “non hyperthread cores only” by default, Problem solved, no need to turn HT off, why would u buy an i7 instead an i5 if u want to turn HT off???? Some ppl just buy without making a minimum research…
http://bitsum.com/prolasso.php
There ya go, make sure u download the 64 bits version.

“HT on or off” is one of those system dependent questions.

i mainly play games and browse through the internet, also my CPU naturally heats up alot so i turn HT off to lower my temps (saves 11°C O.O ), vcore and add additional OC potential.
though, if i actually edit some videos, it can get annoying without HT. same goes for playing games while having firefox, skype and a media player and several updates open.
switching it to on or off isn’t a big hassle…takes 10sec to switch BIOS profiles.

don’t ask me why i have a CPU with HT technology in the first place if i have HT off mainly…it just happens to be a part of my system.
though, it does come in handy sometimes.

but if you just intend to play videogames and using a messenger and/or media player in the background, turn HT off, if you want additional OC potential.
otherwise, as already mentioned above, usually, there’s no reason not to have HT on…if HT actually affects performance in GW2, then it’s simply not noticeable.

for some people HT on quads causes issues in this game, a few people over the time i been watching these forums have found disabling it gave them a sizeable fps boot.

others got no boost doing so…..if your fps are really bad, it may be worth a try……then again if your got an intel with HT and its not overclocked your kinda missing out on perf this game needs.

it will run better whit HT on

The purpose of HT is to utilize more of the overall functionality of the core by giving the internal instruction scheduler a 2nd set of code unrelated to the first. This can improve the overall instructions per cycle (IPC) the core is processing.

Now the downside is executing a 2nd thread means all the core oriented caches are now smaller per thread. And it’s the main reason the i7 has additional L3 cache. Cache misses slows the overall IPC and with two threads running, depending on how much memory they want to access, misses can go up thus lowering IPC, even to less than what a single thread but multitasking the two threads that would have happened without HT.

Basically it’s a crap shoot. Sometimes it’s really good giving an extra 20-30%, commonly 10% but on occasion when it’s streaming through lots of memory, negative. Some games really hit memory hard causing a higher chance of cache misses normally and in those cases HT isn’t a plus.

Here’s an explanation on HT with picture from back when the i7-870 came out.

http://www.trustedreviews.com/Intel-Core-i7-870---Core-i5-750_PC-Component_review_the-science-bit-cont_Page-3

But it’s up to you to try it with your system and see which is better. It really depends on what else is running on your system.

Rampage.7145:

Download “process Lasso” it is a very advanced task manager (what windows should have if wasn’t an OS made for kitten ppl), it will allow u to set up the games to use the “non hyperthread cores only” by default, Problem solved, no need to turn HT off, why would u buy an i7 instead an i5 if u want to turn HT off???? Some ppl just buy without making a minimum research…
http://bitsum.com/prolasso.php
There ya go, make sure u download the 64 bits version.

thank you. finally, someone else who knows the power of process lasso.

disabling multithreading as a performance gain is a myth. The problem is how Windows
handles core parking. just un-park those cores during gaming and you will be good to go.

God Of Fissures.8627:

This principle applies to nearly every game. I’ll explain how Hyperthreading works and why it is detrimental to gamers.

Newer games like Battlefield 4 and Crysis 3 all benefit from having HT enabled, and they benefit greatly. This is especially true for Crysis 3, that has been known to gain performance increase in the 20% – 30% range with HT on compared to leaving it off (here’s one test that confirms this: http://maldotex.blogspot.se/2013/02/hyperthreading-and-real-custom-graphics.html )

None of my games benefits from disabling HT in anyway measurable, but like I said, when it comes to really demanding, multithreaded games, HT can give a major boost.

People that claim they see huge performance gains by disabling HT should check out the rest of their system configurations, since most likely something is misconfigured.

General performance overall when it comes to multitasking and lots of small tasks, decoding and so on, all benefit from HT.

Conclusion: If you have it, leave it ON!

HT only causes performance issues for heavily SINGLE threaded applications. As HT is a ‘virtual Thread’ Pined to a physical Core. If that single thread is using 80%+ of a single core, and HT is enabled, you are reducing the over all system performance as your OS will be throwing threads into HT. Whether or not the Physical Cores are overloaded.

For applications that are properly multi-threaded, HT will increase performance as each physical Core will handle 2 Threads. Instead of additional threads waiting for resources to become available.

GW2 is a great example of a poorly coded Single Threaded application. Since the main rendering thread is single, and it tends to use 80%+ of its physical Resource, HT will not overly help for it. And in some cases (1080p, Full on Details, Super-Sampling…ect) HT will hurt performance.

But, HT aside as there is also the FX modules that need to be considered for this discussion, you should leave the additional threads enabled. Instead of disabling them, use Process Lasso/Affinity settings to control what applications ‘peg’ to when it comes to physical resources.

Over all, your OS will benefit over the additional threads then ANYTHING else.