I can confirm, disabling hyperthreading reduced LOT of stuttering.

Unfortunately I'm not able to disable HT in my XPS 15 Bios :-/

Would it make a difference if I just disable the HT cores for the launcher.exe of CoD? :confused:

If I turn off HT now, will I have to turn it back on once we get multi-core support?

Whiskey

Multicore processing isn't the same as Intel HyperCrap! :grin:

You have an AMD CPU, you don't have HyperCrap!

Hypercrap? I smell a flame war in the kindling...

Hmm, well my Core i5 never had any hyperthreading, which explains why the game has always run fine for me I guess!

No flame. We today have X4, X6, X8 CPUs, and this proprietary tech from Intel have issues regards performance with some apps. We AMD customers don't need to bother ;)

I don't see any difference with HT on and HT off in CoD. In fact, none of my sims get stutters related to HT.

There is little utility here: http://technet.microsoft.com/en-us/s.../cc835722.aspx , which will show cpu mapping if it is run with "-c" parameter.

Usual mapping for i7 9xx with HT is: A=[0,1], B=[2,3], C=[4,5], D=[6,7]. This means that virtual CPUs 0 and 1 are in fact a single hyperthreaded core and so on. This is most common mapping, but it is done by BIOS, so mainboard manufacturer still has ability to make a surprise. It is important to know the mapping surely if you are going to use HT with manually set affinity masks.

HT is pretty nice thing, but it requires certain conditions for noticeable performance gains, whose are usually achievable only by specially designed applications, however even non HT aware applications usually benefit from HT to some extent.

Most problems start when two logical cores, belonging to same physical core, are treated as fully separate physical cores. I.e., if two heavy threads are put on cores 6 and 7 (same physical core), then they will run very slow, if compared to situation when they are put on cores 4 and 6 (2 separate physical cores). This must be always be taken into account, when setting affinity masks, and setting manual affinity masks is a must sometimes (i.e. thread scheduler likes to condense everything on to single physical CPU, while thinking it is 2 CPUs).

Those who have stutters with HT on, have you tried running with HT and custom affinity mask? I.e. putting CoD on cores 2, 4, 6 (counting from 0).

Wow, thank you Zalty for this information.

Until now, we had Process Affinity =
=1 - core 0
=2 - core 1
=3 - core 0+1
=4 - core 2
=5 - core 0+2
=6 - core 1+2
=7 - core 0+1+2
=8 - core 3
=9 - core 0 + 3
=10 - core 1 + 3
=11 - core 0 + 2 + 3
=12 - core 2 + 3
=13 - core 0 + 2 + 3
=14 - core 1 + 2 + 3
=15 - core 0 + 1 + 2 + 3

I am very bad with (binary maths) so, what number do we need in order to make the game use cores 0+2+4+6 ????

~S~

By manually changing the process affinity mask threw the taskmanager.