<div dir="ltr">I'll compile the times in a pdf when I get a chance, but on my i7 2600k @ 4.6GHz setting manually to 8 threads was faster for every test in the cycles suite than using auto-detect.<div><br></div><div>Matt Heimlich</div>
</div><div class="gmail_extra"><br><br><div class="gmail_quote">On Sat, Jul 6, 2013 at 3:48 PM, Thomas Dinges <span dir="ltr"><<a href="mailto:blender@dingto.org" target="_blank">blender@dingto.org</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi,<br>
some time ago (summer 2012), we changed the amount of threads for CPU<br>
rendering to "number of threads + 1", when using the threads "Auto<br>
Detect" feature, which is default.<br>
This topic has been raised a couple of times since then, especially<br>
users were wondering why they have e.g. 5 tiles on screen, although they<br>
only have 4 CPU cores.<br>
<br>
I did some tests today, and it seems there is no real performance gain<br>
by doing "threads + 1". It would be good though to re-confirm this on 8<br>
thread systems too (Core i7, Hyper Threading).<br>
<br>
Here my benchmark results:<br>
<a href="http://archive.dingto.org/2013/blender/code/Cycles_Thread_Bench.pdf" target="_blank">http://archive.dingto.org/2013/blender/code/Cycles_Thread_Bench.pdf</a><br>
<br>
Best regards,<br>
Thomas<br>
<span class="HOEnZb"><font color="#888888"><br>
--<br>
Thomas Dinges<br>
Blender Developer, Artist and Musician<br>
<br>
<a href="http://www.dingto.org" target="_blank">www.dingto.org</a><br>
<br>
_______________________________________________<br>
Bf-cycles mailing list<br>
<a href="mailto:Bf-cycles@blender.org">Bf-cycles@blender.org</a><br>
<a href="http://lists.blender.org/mailman/listinfo/bf-cycles" target="_blank">http://lists.blender.org/mailman/listinfo/bf-cycles</a><br>
</font></span></blockquote></div><br></div>