9 ms·

They already have a mobile chip that is as fast as an active-thermally cooled notebook chip.

fock 6y ago
so could you provide some actual, open-source basic benchmarks. And not strange, opaque geekbench results... I guess AMD is fine for me (as is my old Intel-notebook) and I'll just wait for POVray, GROMACS and Co. EDIT: And well, I noticed, supposedly Anandtech ran SPECint2006 on the A13 (and numerous other chips) - they ran it with WSL for x86 (because running on a dozen Android things is easier than running a standard benchmark on Linux/Windows ofc). You find the results here: https://images.anandtech.com/doci/14892/spec2006-global-overview.png https://images.anandtech.com/doci/14892/spec2006-global-over... - I guess (not sure, because it's for some reason not cleary marked and mentioned...) these are SPECint2006-results. So, let's check them for validity (because WSL is no problem and it matches Linux ofc); just looking at an i7-6700K (which is a little bit behind the i9-9900K they supposedly ran on): https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160108-38634.html https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160... - marginal worse performance than @anandtech in some benchmarks, but that's with an older CPU and an older arch! And then there are the 3 or 4 benchmarks which are just way off. Makes one wonder, what they really did (because of course, installing CentOS and running SPEC on native Linux is too much of a hassle, when running and compiling on 8 ARM-platforms!?) EDITEDIT: it's even worse for SPECfp2006: https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160107-38616.html https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160... [well, here the old 6700K suddenly sometimes is twice as fast as the 9900K and 3x as fast as the A13 (and yeah the story of the 2.8GHz-low-power-chip drawing circles around a 4.5GHz-HF-part just didn't sound convincing in the first place...)]
- Veedrac 6y ago
  The official results from spec.org have a bunch of cheating, eg. exploiting undefined behaviour to run a benchmark improperly. AnandTech uses a consistent compiler (Clang, not ICC) without settings to exploit this, hence the divergence. Andrei mentions this here: https://www.realworldtech.com/forum/?threadid=187314&curpostid=187974 https://www.realworldtech.com/forum/?threadid=187314&curpost...
  - KMag 6y ago
    When I started at Google, I sat next to a guy who used to write compilers for DEC and Intel. I asked him, given the huge amount Google spends on hardware and electricity, if he thought that switching to ICC was worth while. His answer was basically that ICC is tuned to maximally exploit undefined behavior for marketing purposes and he wouldn't want to use it in production, at least without heavily tweaking flags to disable some optimizations. ICC gets most of its speed advantages by enabling optimizations that are present in GCC/Clang, but deemed too dangerous to turn on by default.
  - fock 6y ago
    clang with "-Ofast"; I really wonder, which other options are there?! And imho this just doesn't explain the 200% difference? And some other things which are bugging me: - can you only optimize for A53 on Android with the big.LITTLE-configurations (they do!)? - so they cross-compiled an AMD64-producing gcc 3.2 with Xcode 10 on MacOS-X for ARM? impressive.
alkonaut 6y ago
Isn't that for specific benchmarks though such as some geekbench/specint or web browsing benchmarks? I worry about non-gpu floating point for example. There is so much hand-optimized AVX/SSE code out there in big apps.
- klodolph 6y ago
  There’s a fair bit of AVX/SSE code out there, but these days the vast bulk of AVX/SSE code is generated by the autovectorizer and that’s mostly going to work on NEON without a hitch. Clang enables the autovectorizer at -O2 by default. I’d be interested in estimates of how much hand-written AVX/SSE your computer actually runs. The apps I’ve seen usually have a fairly small core of AVX/SSE code.
  - wolf550e 6y ago
    But is the bulk of AVX code by time spent running, code that was generated by autovectorizer? The SIMD in openssl and ffmpeg is written by hand. I bet the code that spends a lot of time on the CPU, especially the code that runs a lot while humans are waiting, is written by hand.
    - throwaway5792 6y ago
      Those should have AArch64 versions written. AArch64 is old now, it's not some niche architecture.
      - wolf550e 6y ago
        Desktop productivity content creation apps have never before needed ARM versions, so many probably don't have ARM specific optimizations, and some probably have x86 specific code that is just enabled by default. The memory model differences are going to be painful to debug, I think ("all-the-world's-a-VAX syndrome" is now "all the world's a Pentium/x86-64").
  - berkut 6y ago
    They're admittedly not applications most users run every day, but many multimedia applications (audio processing, encoding, decoding) is mostly done with hand-crafted instrinsics, the same goes for video stuff. In an even more niche area (high-end VFX apps, like compositors, renderers) SSE/AVX intrinsics are used quite a bit in performance-critical parts of the code, and auto-vectorisers can't yet do as good a job (they're pretty useless at conditionals and masking).
jl6 6y ago
"As fast" on specific curated use cases. Show me an Apple chip that beats any laptop on 7zip.
- r00fus 6y ago
  Is this a joke, what kind of usage benchmark is 7zipping large numbers of files?
  - AlexandrB 6y ago
    I think the point is that it won’t be as fast in applications that Apple didn’t anticipate.
  - chipotle_coyote 6y ago
    I believe it is what the poster you are replying to would call "a specific curated use case." (Semi-seriously, I don't know anyone who uses a Unix(-like) system who uses 7zip, although I'm sure they're out there. For the record, I just unzipped a 120M archive on both my 2020 Core i7 MacBook Air and my 2018 (last-gen) iPad Pro and as near as I can tell the iPad was faster actually extracting the files, but had an extra second or so of overhead from the UI.)
    - ac29 6y ago
      > I don't know anyone who uses a Unix(-like) system who uses 7zip 7zip is an implementation of LZMA, like xz. So, different names and file format details, but essentially the same algorithm.
      - user5994461 6y ago
        Correct. 7zip is a LZMA compressor. The common equivalent command line tool on Linux is xz. Linux distributions have been using xz compression for all packages (replacing gzip). So to the question of how relevant is xz/lzma/7zip performance to day to day task, is it's a lot relevant. The successor will probably be zstd in the coming years. https://www.phoronix.com/scan.php?page=news_item&px=Fedora-31-Zstd-RPM-Change https://www.phoronix.com/scan.php?page=news_item&px=Fedora-3...

fock 6y ago

so could you provide some actual, open-source basic benchmarks. And not strange, opaque geekbench results... I guess AMD is fine for me (as is my old Intel-notebook) and I'll just wait for POVray, GROMACS and Co. EDIT: And well, I noticed, supposedly Anandtech ran SPECint2006 on the A13 (and numerous other chips) - they ran it with WSL for x86 (because running on a dozen Android things is easier than running a standard benchmark on Linux/Windows ofc). You find the results here: https://images.anandtech.com/doci/14892/spec2006-global-overview.png https://images.anandtech.com/doci/14892/spec2006-global-over... - I guess (not sure, because it's for some reason not cleary marked and mentioned...) these are SPECint2006-results. So, let's check them for validity (because WSL is no problem and it matches Linux ofc); just looking at an i7-6700K (which is a little bit behind the i9-9900K they supposedly ran on): https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160108-38634.html https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160... - marginal worse performance than @anandtech in some benchmarks, but that's with an older CPU and an older arch! And then there are the 3 or 4 benchmarks which are just way off. Makes one wonder, what they really did (because of course, installing CentOS and running SPEC on native Linux is too much of a hassle, when running and compiling on 8 ARM-platforms!?) EDITEDIT: it's even worse for SPECfp2006: https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160107-38616.html https://www.spec.org/cpu2006/results/res2016q1/cpu2006-20160... [well, here the old 6700K suddenly sometimes is twice as fast as the 9900K and 3x as fast as the A13 (and yeah the story of the 2.8GHz-low-power-chip drawing circles around a 4.5GHz-HF-part just didn't sound convincing in the first place...)]

Veedrac 6y ago
The official results from spec.org have a bunch of cheating, eg. exploiting undefined behaviour to run a benchmark improperly. AnandTech uses a consistent compiler (Clang, not ICC) without settings to exploit this, hence the divergence. Andrei mentions this here: https://www.realworldtech.com/forum/?threadid=187314&curpostid=187974 https://www.realworldtech.com/forum/?threadid=187314&curpost...
- KMag 6y ago
  When I started at Google, I sat next to a guy who used to write compilers for DEC and Intel. I asked him, given the huge amount Google spends on hardware and electricity, if he thought that switching to ICC was worth while. His answer was basically that ICC is tuned to maximally exploit undefined behavior for marketing purposes and he wouldn't want to use it in production, at least without heavily tweaking flags to disable some optimizations. ICC gets most of its speed advantages by enabling optimizations that are present in GCC/Clang, but deemed too dangerous to turn on by default.
- fock 6y ago
  clang with "-Ofast"; I really wonder, which other options are there?! And imho this just doesn't explain the 200% difference? And some other things which are bugging me: - can you only optimize for A53 on Android with the big.LITTLE-configurations (they do!)? - so they cross-compiled an AMD64-producing gcc 3.2 with Xcode 10 on MacOS-X for ARM? impressive.

alkonaut 6y ago

Isn't that for specific benchmarks though such as some geekbench/specint or web browsing benchmarks? I worry about non-gpu floating point for example. There is so much hand-optimized AVX/SSE code out there in big apps.

klodolph 6y ago
There’s a fair bit of AVX/SSE code out there, but these days the vast bulk of AVX/SSE code is generated by the autovectorizer and that’s mostly going to work on NEON without a hitch. Clang enables the autovectorizer at -O2 by default. I’d be interested in estimates of how much hand-written AVX/SSE your computer actually runs. The apps I’ve seen usually have a fairly small core of AVX/SSE code.
- wolf550e 6y ago
  But is the bulk of AVX code by time spent running, code that was generated by autovectorizer? The SIMD in openssl and ffmpeg is written by hand. I bet the code that spends a lot of time on the CPU, especially the code that runs a lot while humans are waiting, is written by hand.
  - throwaway5792 6y ago
    Those should have AArch64 versions written. AArch64 is old now, it's not some niche architecture.
    - wolf550e 6y ago
      Desktop productivity content creation apps have never before needed ARM versions, so many probably don't have ARM specific optimizations, and some probably have x86 specific code that is just enabled by default. The memory model differences are going to be painful to debug, I think ("all-the-world's-a-VAX syndrome" is now "all the world's a Pentium/x86-64").
- berkut 6y ago
  They're admittedly not applications most users run every day, but many multimedia applications (audio processing, encoding, decoding) is mostly done with hand-crafted instrinsics, the same goes for video stuff. In an even more niche area (high-end VFX apps, like compositors, renderers) SSE/AVX intrinsics are used quite a bit in performance-critical parts of the code, and auto-vectorisers can't yet do as good a job (they're pretty useless at conditionals and masking).

jl6 6y ago

"As fast" on specific curated use cases. Show me an Apple chip that beats any laptop on 7zip.

r00fus 6y ago
Is this a joke, what kind of usage benchmark is 7zipping large numbers of files?
- AlexandrB 6y ago
  I think the point is that it won’t be as fast in applications that Apple didn’t anticipate.
- chipotle_coyote 6y ago
  I believe it is what the poster you are replying to would call "a specific curated use case." (Semi-seriously, I don't know anyone who uses a Unix(-like) system who uses 7zip, although I'm sure they're out there. For the record, I just unzipped a 120M archive on both my 2020 Core i7 MacBook Air and my 2018 (last-gen) iPad Pro and as near as I can tell the iPad was faster actually extracting the files, but had an extra second or so of overhead from the UI.)
  - ac29 6y ago
    > I don't know anyone who uses a Unix(-like) system who uses 7zip 7zip is an implementation of LZMA, like xz. So, different names and file format details, but essentially the same algorithm.
    - user5994461 6y ago
      Correct. 7zip is a LZMA compressor. The common equivalent command line tool on Linux is xz. Linux distributions have been using xz compression for all packages (replacing gzip). So to the question of how relevant is xz/lzma/7zip performance to day to day task, is it's a lot relevant. The successor will probably be zstd in the coming years. https://www.phoronix.com/scan.php?page=news_item&px=Fedora-31-Zstd-RPM-Change https://www.phoronix.com/scan.php?page=news_item&px=Fedora-3...