Lunar Lake's iGPU: Debut of Intel's Xe2 Architecture

https://chipsandcheese.com/p/lunar-lakes-igpu-debut-of-intels

by mfiguiere • 2 years ago

131 63 2 years ago

SG-• 2 years ago

i wish they covered things like x264/x265/av1/etc encoding/decoding performance and other benefits that aren't just gaming.

hggigg2• 2 years ago

100% agree with that. x265 transcoding gets done on my MBP regularly so I’d like to see that as a comparison point.

adgjlsfhk12• 2 years ago

what actually uses x265? I thought pretty much everyone used AV1 for their next gen codec.

TiredOfLife• 2 years ago

x265 is a cpu based H.265 encoder and is not accelerated.

booi• 2 years ago

It’s probably just not that interesting. There’s generally a proprietary encode/decode pipeline on chip. It can generally handle most decode operations with CPU help and a very narrow encoding spec mostly built around being able to do it in realtime for broadcast.

Most of the video you encode on a computer is actually all in software/CPU because the quality and efficiency is better.

ramshanker• 2 years ago

>> It can generally handle most decode operations with CPU help and a very narrow encoding spec.

This is so much spot on. Video coding specs are like a "huge bunch of tools" and encoders get to choose whatever subset-of-tools suits them. And than hardware gets frozen for a generation.

Dalewyn2• 2 years ago

Most of the video you encode on a computer is actually all in software/CPU because the quality and efficiency is better.

That was the case up to like 5 to 10 years ago.

These days it's all hardware encoded and hardware decoded, not the least because Joe Twitchtube Streamer can't and doesn't give a flying fuck about pulling 12 dozen levers to encode a bitstream thrice for the perfect encode that'll get shat on anyway by Joe Twitchtok Viewer who doesn't give a flying fuck about pulling 12 dozen levers and applying a dozen filters to get the perfect decode.

vbezhenar• 2 years ago

Most of the video you encode on a computer is actually all in software/CPU because the quality and efficiency is better.

I don't think that's true. I bought a Thinkpad laptop, installed Linux and one of my issues was that watching youtube video put CPU onto 60%+ load. The same with Macbook barely scratched CPU at all. I finally managed to solve this issue by installing Arch. When everything worked as necessary, CPU load was around 10%+ for the same video. I didn't try Windows but I'd expect that things on Windows would work well.

So most of the video for average user probably is hardware decoded.

KronisLV• 2 years ago

Most of the video you encode on a computer is actually all in software/CPU because the quality and efficiency is better.

It depends on what you care about more, you don't always need the best possible encoding, even when you're not trying to record/stream something real time.

For comparison's sake, I played around with some software/hardware encoding options through Handbrake with a Ryzen 5 4500 and Intel Arc A580. I took a 2 GB MKV file of about 30 minutes of footage I have laying around and re-encoded it with a bunch of different codecs:

  codec   method   time     speed     file size   of original
  H264    GPU      04:47    200 fps   1583 MB     77 %
  H264    CPU      13:43    80 fps    1237 MB     60 %
  H265    GPU      05:20    206 fps   1280 MB     62 %
  H265    CPU      ~30:00   ~35 fps   would take too long
  AV1     GPU      05:35    198 fps   1541 MB     75 %
  AV1     CPU      ~45:00   ~24 fps   would take too long

So for the average person who wants a reasonably fast encode and has an inexpensive build, many codecs will be too slow on the CPU. In some cases, close to an order of magnitude, whereas if you do encode on the GPU, you'll get much better speeds, while the file sizes are still decent and the quality of something like H265 or AV1 will in most cases seem perceivably better than H264 with similar bitrates, regardless of whether the encode is done on the CPU or GPU.

So, if I had a few hundred of GB of movies/anime locally that I wanted to re-encode to make it take up less space for long term storage, I'd probably go with hardware H265 or AV1 and that'd be perfectly good for my needs (I actually did, it went well).

Of course, that's a dedicated GPU and Intel Arc is pretty niche in of itself, but I have to say that their AV1 encoder for recording/streaming is also really pleasant and therefore I definitely think that benchmarking this stuff is pretty interesting and useful!

For professional work, the concerns are probably quite different.

wcfields2• 2 years ago

I agree, I never really cared about QSV as an Intel feature until I started doing Livestreams, using Plex/Jellyfin/Emby, and virtualizing/homelab work.

WaxProlix• 2 years ago

QuickSync passthrough should get you everything you need on i3+ chips. It's basically intel's only selling point in the homelab/home server space, and it's a big one.

[Edit: I think I initially misread you - but I agree, it's a huge differentiator]

wtallis2• 2 years ago

Video encode and decode aren't really GPU functions. They're totally separate IP blocks from the 3D graphics/vector compute part of the GPU. On Intel's previous laptop processor generation (Meteor Lake), the video encode and decode blocks were on an entirely different piece of silicon from the GPU.

adrian_b2• 2 years ago

True. The display controller is also a different block, separated from the GPU and from the video codecs.

While on Lunar Lake the GPU and the video codec block are on the same tile, they are still in different locations on the compute tile.

In the new Arrow Lake S desktop CPU, to be announced tomorrow, the GPU is extracted on a separate tile, like in Meteor Lake, while the other two blocks related to video output, i.e. the video codec block and the display controller block, are located on a tile that contains the memory controller and a part of the peripheral interfaces and which is made using a lower-resolution TSMC process than the CPU and GPU tiles.

jsheard• 2 years ago

Benchmarking hardware encode is also a pretty specialized rabbit hole since it's not just the performance that varies, but also the quality of the results.

dyingkneepad• 2 years ago

the video encode and decode blocks were on an entirely different piece of silicon from the GPU.

As far as I understand this is not true. It's a different engine within the graphics device, and it shares the execution units.

pa7ch• 2 years ago

Agreed, my laptop burns a lot of battery on AV1 video and I'd like information on how chips with AV1 decode perform with chrome.

Remnant44• 2 years ago

As mentioned in other responses, that part of the GPU simply isn't interesting from an architectural perspective, which is what Chips and Cheese is all about.

GPU compute performance is both technically interesting, and matters to much more than simply gaming!

transpute5• 2 years ago

Xe2, Intel is looking to use the same graphics architecture across their product stack.. integrated GPUs as a springboard into the discrete GPU market.

Linux support for Xe2 and power management will take time to mature, https://www.phoronix.com/forums/forum/linux-graphics-x-org-d...

Xe SR-IOV improves VM graphics performance. Intel dropped Xe1 SR-IOV graphics virtualization in the upstream i915 driver, but the OSS community has continued improvement in an LTS fork, making steady progress, https://github.com/strongtz/i915-sriov-dkms/commits/master/ & https://github.com/Upinel/PVE-Intel-vGPU?tab=readme-ov-file.

iforgotpassword• 2 years ago

Aww man this is so disappointing. Intel has a pretty good track record with their Linux drivers. Too bad cost-cutting seems to have reached driver development too.

transpute5• 2 years ago

Intel has been developing a new graphics driver stack for Xe, which will officially support SR-IOV from Xe2 onward, https://www.phoronix.com/news/Intel-New-Xe-Linux-Driver. It makes sense to focus Intel resources on the new hardware and driver architecture, but thanks to OSS, the existing stable driver can also be improved by community contributions.

transpute5• 2 years ago

Impact appears to be limited, https://www.phoronix.com/news/Intel-Maintainers-Linux-Depart

shadeslayer5• 2 years ago

The issue that phoronix is facing might be due to a power management bug that is not related to the driver at all.

teruakohatu• 2 years ago

Intel dropped Xe1 SR-IOV graphics virtualization in the upstream i915 driver,

I missed this. Wow this is disappointing.

reginald78• 2 years ago

I remember being somewhat excited for Intel dGPUs since I had a real interest in a card that could do GVT-g and also might have super low idle power consumption like their iGPUs that would fit well with my VM server. We ended up with GVT-g canceled and promising of SR-IOV coming eventually and dGPUs with atrocious idle power consumption!

shadeslayer5• 2 years ago

Not sure if we need to support SRIOV on the HW. VirtIO GPU native contexts should be good enough for most consumers.

I imagine SRIOV would be useful for more advanced usecases

cassepipe• 2 years ago

So the state of Xe support on Linux is pretty good ? Is it worth it to run Linux on Alder Lake, can it take advantage of the full power of the iGPU ?

Sakos3• 2 years ago

Lunar Lake gaming performance is incredible on Windows. It makes me want the Steam Deck 2 to be based on the next Intel platform. That said, the Linux graphics drivers are terrible (https://www.phoronix.com/review/lunar-lake-xe2) and the Phoronix benchmarks for Lunar Lake overall (outside of gaming: https://www.phoronix.com/review/core-ultra-7-lunar-lake-linu...) showed terrible performance in all sorts of aspects, jesus. Xe2 is a huge win, the rest not so much.

automatic61312• 2 years ago

MSI Claw 2 might, given it's original is Meteor Lake based. But it sold like ** so there may not be a successor

Sakos3• 2 years ago

Did the first claw even sell well? That said, the Steam Deck competitors aren't interesting to me without the touchpads and four back buttons.

skavi• 2 years ago

GPU benchmarks in TFA are run on Windows: https://open.substack.com/pub/chipsandcheese/p/lunar-lakes-i...

Sakos3• 2 years ago

Weird. I've seen far better results elsewhere.

formerly_proven• 2 years ago

With totally new hardware platforms things often take a minute to really work (even on Windows).

KeplerBoy2• 2 years ago

Here's hoping ARM on the desktop/laptop finally takes off and we see Nvidia returning to these market segments.

Their Tegra chips could do a lot in these laptop / handheld gaming devices.

chmod775• 2 years ago

That's a big hit in performance compared to the AMD chip. Just to save $100 on a $1700 notebook? Sadly the article didn't get into power draw too much. That might've been much more interesting.

phkahler• 2 years ago

> Sadly the article didn't get into power draw too much.

They covered power quite a bit, but claimed the biggest power draw comes from memory access. I got the impression they were blaming AMDs increased memory bandwidth on their smaller cache size and hence a form of inefficiency. But higher frame rates are going to require more memory accesses. The smaller cache should have less impact on the number of writes needed. IMHO just some top line power consumption numbers are good, but trying to get into why one is higher than the other seems fruitless.

nuz• 2 years ago

Nvidias moat is so enormous

Wytwwww2• 2 years ago

What moat? Nvidia is barely even competing in the same Xe2 is in. Their laptop GPUs aren't particularly spectacular and aren't at all suitable for low-power use cases.

Lunar Lake's iGPU: Debut of Intel's Xe2 Architecture

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