Is encoding done by CPU or GPU?

[APMcG]

Hi, I have a not-very-powerful host and an AMD E300 netbook client (see below), and I have been playing around with getting Trine 1 and 2 working on the client. Can only get a playable frame rate when the resolution dips down to about 1024*768 (no AA, vert sync etc), but non-streaming I can get a good framerate at 1440*900 at high detail.

Incrementally increasing resolution and effects, I get error 'slow encode' before 'slow encode/decode', so I would like to know whether upgrading the GPU could be expected to improve streaming encoding, or if this is something handled by the CPU. Would also like to know what the maximum resolution/fps might be that I could expect from my laptop. Ideally I'd like to hook the laptop up to an HD TV, but that might be pie in the sky.

Host:
AMD Athlon X2 245 @2.9ghz
4gb DDR2 ram @ 800mhz
HD 4650 gpu, 1gb vram

Client:
AMD E300 @ 1.33ghz
4gb ram
HD6310

Sorry if this has already been addressed in another post, please point me at it if you know.

I can't tell you how cool I think this feature is, even if I don't have it working as I'd like it yet. Thanks in advance for help

[APMcG]

Note: I have 'hardware encoding' and 'hardware decoding' ticked. I presume these mean that the GPU in each is dealing with encoding/decoding.

Is it possible to see from the streaming logs where bottlenecks are occuring?

[Martelol]

As far as I'm aware, hardware encoding is currently limited to CPUs supporting Quicksync (Intel Sandy Bridge or newer). I imagine GPUs with hardware encoders (Radeon 7000 series and newer, Geforce 600 series and newer) will get hardware encoding support soonish.

You CPU and GPU both lack a hardware encoder, and your CPU is pretty lackluster for software encoding, sorry to say.

[SilentHorizon]

wait, so I thought hardware acceleration supported nvidia CUDA already?

[APMcG]

Interesting that you say that my CPU and GPU both lack a hardware encoder, because unticking hardware encoding/decoding does make a noticeable difference to speed of encoding/decoding.

I'm considering a radeon 7870 or R9 270 as a first upgrade, would this be wasted on the current setup?

[powerarmour]

Originally posted by HBZK100:

wait, so I thought hardware acceleration supported nvidia CUDA already?

Decoding yes (DXVA on Windows, VDPAU on Linux), not encoding yet.

And to the OP, an Athlon X2 isn't going to be enough for encoding unfortunately, quad core recommended at the moment.

[SilentHorizon]

was wondering about that. because my specs are low enough that hardware acceleration is a required to stream.

[Shrike]

My understanding is that up until recently, all encoding was done by software, aka using the CPU to run a software based encoding method. Valve added hardware encoding support for Quicksync, for Intel CPU's that support this method. I don't think Steam streaming has hardware supported encoding for NVENC (Nvidia hardware encoding, as used by Nvidia Gamestream) or for AMD VCE (AMD's version).

I believe that ticking the hardware encoding option does nothing if you don't have a Quicksync CPU, so it doesn't matter if you have an Nvidia or AMD card. Furthermore, I have an i5-3570k and have quicksync enabled, and the hardware encoding is WORSE (blockier, and choppier, and with more latency) than software encoding. In fact Software encoding seems to work almost perfectly for me, so I don't intend to ever use hardware encoding. I suppose if you have a weak CPU, then software encoding may not be great, and future support for AMD/Nvidia hardware encoding may help with this. Quicksync certainly seems to work poorly for me.

As for hardware decoding, I don't really know much about that. It doesn't seem to make much difference, on or off for me. If my understanding of any of the above is incorrect, I hope someone will please say so. I am hoping that Steam will implement streaming to Android for those with AMD GPUs (limelight already does it for those with Nvidia).

[SilentHorizon]

I personally have an i5-2410M sandy bridge as the host pc, so it does run quicksync. However, my client pcs pentium D doesn't have the horsepower to host to my pc, so useing the more powerful gpus cuda cores would be so much faster.

Your right though, I do see some choppiness and lag in portal 2 when streaming on client pc. The devs will probably fix this soon however.

[APMcG]

Originally posted by powerarmour:

And to the OP, an Athlon X2 isn't going to be enough for encoding unfortunately, quad core recommended at the moment.

Thanks for the reply, that's kind of what I suspected :(

I'm confused now about whether hardware encoding/decoding is managed game-specifically. I tried Spec Ops: the line, and having it ticked on host/client made no difference - I still got a max playable res of 848*480. But with Trine, having it ticked on the client made a huge difference - playable at 1280*720, with occasional 'slow encode' error. Unticked, was unplayable even at low res due to 3-4 second lag, although I could see on the host that the input lag was virtually nothing.

[SilentHorizon]

Originally posted by stutta:

Originally posted by powerarmour:

And to the OP, an Athlon X2 isn't going to be enough for encoding unfortunately, quad core recommended at the moment.

Thanks for the reply, that's kind of what I suspected :(

I'm confused now about whether hardware encoding/decoding is managed game-specifically. I tried Spec Ops: the line, and having it ticked on host/client made no difference - I still got a max playable res of 848*480. But with Trine, having it ticked on the client made a huge difference - playable at 1280*720, with occasional 'slow encode' error. Unticked, was unplayable even at low res due to 3-4 second lag, although I could see on the host that the input lag was virtually nothing.

Could you upgrade to an x4 750k or somethin along those lines? They are really cheap.

[APMcG]

Unfortunately not, my mobo has AM2+ socket. Upgrading CPU to something really good means upgrading mobo and RAM too, hence why I'd like to upgrade the gfx card first if it would be worth it. Can't really justify a full upgrade just yet but I have my eye on some Phenom/Opteron processors on ebay

[APMcG]

Another question re upgrades: is the FM2 socket any better than AM3/AM3+? I'm considering a Phenom x6 cpu which I could fit in my current board, then at some point upgrade to one that supports ddr3 (and not have to upgrade cpu)

[powerarmour]

Originally posted by stutta:

Another question re upgrades: is the FM2 socket any better than AM3/AM3+? I'm considering a Phenom x6 cpu which I could fit in my current board, then at some point upgrade to one that supports ddr3 (and not have to upgrade cpu)

I think an X6 would very likely solve the problem, at least until AMD VCE hardware encoding is supported (if it's added mind...).

With only two cores/threads, you are basically running the game on one and encoding on the other, not exactly an ideal solution. With an X6 it should run the game on three cores and encode on the other three (likewise with a 4C/8T Core i7, it'll run the game on four threads, and encode with the other four etc)

Software decode on a client is a bit different, as far as I can tell it uses all threads/cores except one (you need one for the UI/System). So again if you don't have DXVA or VDPAU H.264 decoding capability, the more cores/threads the better.

[SilentHorizon]

Originally posted by stutta:

Another question re upgrades: is the FM2 socket any better than AM3/AM3+? I'm considering a Phenom x6 cpu which I could fit in my current board, then at some point upgrade to one that supports ddr3 (and not have to upgrade cpu)

Their pretty much equal, because fm2 is newer, thus you will have newer features. However, your gona be stuck with apus on fm2 socket, so am3+ would be a wiser choice if you need high performance cpus.

[APMcG]

Well I've ordered the X6 cpu, I look forward to seeing how it fares with streaming and general performance. From looking at what's available it does seem like the FM2 socket is only for A series APUs and for quite low performance CPUs, not a direction I want to take.