[x264-devel] hyperthreading and latency

[Jason Garrett-Glaser]

On Sun, Oct 17, 2010 at 4:56 AM, aviad rozenhek <aviadr1 at gmail.com> wrote:
>> > I think the answer is no and that the default value of X264_THREADS_AUTO
>> > could work even better on hyper-threaded systems if hyper-threading are
>> > not
>> > considered an actual CPU.
>>
>> If you need low latency, you should use sliced threads, as explained
>> in the documentation.
>>
>> Tests show that hyperthreading improves performance by about 25%
>> overall under normal conditions.  Latency is completely unrelated to
>> performance, except in that if you force low latency settings, you
>> will hurt performance.
>>
>> Dark Shikari
>
> Thanks,
> What I actually need is to know in advance how much latency x264 is
> introducing, while keeping the great quality associated with the default
> presets and normal threads.

Then don't use auto threads.

> additionally, I'm asking whether using 12 threads instead of 6 on a 4-core
> i7 improves performance?

Let me quote myself again then:

>> Tests show that hyperthreading improves performance by about 25%
>> overall under normal conditions.

Dark Shikari