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JAMIL
02-09-2005, 09:04 AM
I have dual Xeon processors with HyperThreading, but when I start to render I see in system performance (WinXP) that only one processor makes render.
Can I use all of my processors; also how about HyperThreading? May be there is some controls there, or plugins, or something...

I use LW 8.0 included in VT4 box.

Regards

Jamil

JML
02-09-2005, 09:13 AM
if you render directly from LW , go inside rendering options
and change the number of threads from 1 to 2 or 4

if you use screamnet, setup 2 rendering nodes .

mattclary
02-09-2005, 09:14 AM
Under Render Options, make sure to use AT LEAST 4 threads. By default, it is set to one, and would give you exactly the results you are seeing.

Tom Wood
02-09-2005, 07:04 PM
if you render directly from LW , go inside rendering options
and change the number of threads from 1 to 2 or 4

if you use screamnet, setup 2 rendering nodes .

Actually you can set up 4 render nodes with dual Xeons. Just be sure 4 graphs appear in Task Manager so you know hyper-threading is turned on. Also, if your scenes are very small and don't have a bunch of radiosity and whatnot, you may find that leaving *multi* threading set to 1 is most efficient when using Screamernet. Otherwise Layout spends more time getting ready to use multi-threading than it is worth.

My scenes take about nine seconds a frame to render just one frame of an animation. With Screamernet, that bumps up to about 12 seconds per frame per node. But with 4 nodes running, it averages out to about 3 seconds per frame at the end. Very cool.

TW

JML
02-09-2005, 08:28 PM
I think it depends on the kind of scene..
sometimes I would run 2 nodes on a single processor machine, but those
scene are very easy and light to render,
but when the scenes are bigger, and the renders take like 5-10 minutes, I think it will gets slower if I run 4 node on a dual machine.. (having 'only' 4gb on it)
but I will look more into it, that's a good idea,
thanks

Captain Obvious
02-10-2005, 06:29 AM
As has been stated, you must turn up the threads. 4 or more minimum to use both processors and HyperThreading.

Speaking of which, are you running XP Home or Pro? I'm fairly sure Home can't use HT.

Tom Wood
02-10-2005, 06:39 AM
I'm no expert at this, but I -think- multi-threading and hyper-threading are independent of each other. Hyper-threading turns on the 'virtual' processor capability of Xeon processors, so you get twice as many render nodes as there are physical processors.

Multi-threading has to do with separating a single render among multiple processors. Since Screamernet works by assigning one frame/render to one render node, I'm not clear that multi-threading is going to apply anyway. Maybe multi-threading is more applicable to print/heavy single image renders rather than multiple frames of animation renders.

TW

Captain Obvious
02-10-2005, 06:46 AM
I'm no expert at this, but I -think- multi-threading and hyper-threading are independent of each other. Hyper-threading turns on the 'virtual' processor capability of Xeon processors, so you get twice as many render nodes as there are physical processors.

Multi-threading has to do with separating a single render among multiple processors. Since Screamernet works by assigning one frame/render to one render node, I'm not clear that multi-threading is going to apply anyway. Maybe multi-threading is more applicable to print/heavy single image renders rather than multiple frames of animation renders.

TW

Yes, that's right. HyperThreading (or SMT) is a processor technology. Multi-threading is something a programmer can add to an application (like dividing rendering on multiple threads).

Since HyperThreading adds multiple virtual CPUs, you also need multi-threading to take advantage of it. It will make it go faster regardless of whether you're rendering a single big frame or a thousand smaller.