CPU Performance & Efficiency: SPEC2006

We’re moving on to SPEC2006, analysing the new single-threaded performance of the new Cortex-A77 cores. As the new CPU is running at the same clock as the A76-derived design of the Snapdragon 855, any improvements we’ll be seeing today are likely due to the IPC improvements of the core, the doubled L3 cache, as well as the enhancements to the memory controllers and memory subsystem of the chip.

Disclaimer About Power Figures Today:

The power figures presented today were captured using the same methodology we generally use on commercial devices, however this year we’ve noted a large discrepancy between figures reported by the QRD865’s fuel-gauge and the actual power consumption of the device. Generally, we’ve noted that there’s a discrepancy factor of roughly 3x. We’ve reached out to Qualcomm and they confirmed in a very quick testing that there’s a discrepancy of >2.5x. Furthermore, the QRD865 phones this year again suffered from excessive idle power figures of >1.3W.

I’ve attempted to compensate the data as best I could, however the figures published today are merely preliminary and of lower confidence than usual. For what it’s worth, last year, the QRD855 data was within 5% of the commercial phones’ measurements. We’ll be naturally re-testing everything once we get our hands on final commercial devices.

In the SPECint2006 suite, we’re seeing some noticeable performance improvements across the board, with some benchmarks posting some larger than expected increases. The biggest improvements are seen in the memory intensive workloads. 429.mcf is DRAM latency bound and sees a massive improvement of up to 46% compared to the Snapdragon 855.

What’s interesting to see is that some execution bound benchmarks such as 456.hmmer seeing a 28% upgrade. The A77 has an added 4th ALU which represents a 33% throughput increase in simple integer operations, which I don’t doubt is a major reason for the improvements seen here.

The improvements aren’t across the board, with 400.perlbench in particular seeing even a slight degradation for some reason. 403.gcc also saw a smaller 12% increase – it’s likely these benchmarks are bound by other aspects of the microarchitecture.

The power consumption and energy efficiency, if the numbers are correct, roughly match our expectations of the microarchitecture. Power has gone up with performance, but because of the higher performance and smaller runtime of the workloads, energy usage has remained roughly flat. Actually in several tests it’s actually improved in terms of efficiency when compared to the Snapdragon 855, but we’ll have to wait on commercial devices in order to make some definitive conclusions here.

In the SPECfp2006 suite, we’re seeing also seeing some very varied improvements. The biggest change happened to 470.lbm which has a very big hot loop and is memory bandwidth hungry. I think the A77’s new MOP-cache here would help a lot in regards to the instruction throughput, and the improved memory subsystem makes the massive 65% performance jump possible.

Arm actually had advertised IPC improvements of ~25% and ~35% for the int and FP suite of SPEC2006. On the int side, we’re indeed hitting 25% on the Snapdragon 865, compared to the S855, however on the FP side we’re a bit short as the increase falls in at around 29%. The performance increases here strongly depend on the SoC and particular on the memory subsystem, compared to the Kirin 990’s A76 implementation the increases here are only 20% and 24%, but HiSilicon’s chip also has a stronger memory subsystem which allows it to gain quite more performance over the A76’s in the S855.

The overall results for SPEC2006 are very good for the Snapdragon 865. Performance is exactly where Qualcomm advertised it would land at, and we’re seeing a 25% increase in SPECint2006 and a 29% in SPECfp2006. On the integer side, the A77 still trails Apple’s Monsoon cores in the A11, but the new Arm design now has been able to trounce it in the FP suite. We’re still a bit far away from the microarchitectures catching up to Apple’s latest designs, but if Arm keeps up this 25-30% yearly improvement rate, we should be getting there in a few more iterations.

The power and energy efficiency figures, again, taken with a grain of salt, are also very much in line with expectations. Power has slightly increased with performance this generation, however due to the performance increase, energy efficiency has remained relatively flat, or has even seen a slight improvement.

Introduction & Specifications System Performance
Comments Locked

178 Comments

View All Comments

  • Alistair - Tuesday, December 17, 2019 - link

    go into your BIOS and run your Intel computer in dual core mode, 2.6Ghz, and come back and tell me it is fast...
  • id4andrei - Wednesday, December 18, 2019 - link

    The software running on these platforms in not identical. Some of it depends on CPU extensions that are not equivalent between platforms. A dual core 2.6 Ghz intel chip will run slower Win10 than an ipad pro would run ios. But you could find a Linux distribution and some oss apps that would run very fast on that 2.6 Ghz dual core intel.
  • Quantumz0d - Tuesday, December 17, 2019 - link

    LOL. You won the most stupid comment here congrats.

    "Android fanatics" so you are an Apple sheep I guess.

    Sandybridge OCed to 4GHz+ still keeps up with a 1080Ti without any issues. That shows how Intel milked and Ryzen caught up due to monopoly. And you are crippling an x86 LGA socket processor to 2.6GHz Dual core and compare with an iPad Pro ? In what usecase ? What is the ultimate goal here ? Lets disable all Lightning and Thunder cores and run 1 Lightning then (You cant do it anyways since Apple is the overlord here). What the actual fuck lmao. Also magically slapping in more A13 cores means x86 Intel and AMD are dead, haha you think this is making a sandwich at home ? I thinm you never heard of Sparc or IBM Power go and read snd get your mind blown on threads but do not compare that to x86 or Apple A series Alien technology please. An iOS cannot even process zip file extraction nor a config file for a VPN. That alone breaks the whole A series King to ashes as its not used in a real computer at all. A psuedo Filesystem and fake filemanager app doesn't make it a proper OS. Unfortunately Android is also following same.retarded path thanks to Apple disease at Google emulating by the abomination called Scoped Storage disaster.

    Let me tell you a secret the laptop you used all are garbage and they are cut down bottom barrel silicon from the failed Desktop chips and so on. The age of rPGA Intel is fucked (Last XM is 4930MX, a true binned Mobile Chip like K) Thanks to BGA greed of Apple infecting Intel for max profits and people to be subverted to use BGA / soldered trash throttling thin and light crappy planned obsolescence HW.

    Let us run a Cinebench on your beloved processor then or lets run a POVray or a H264 Transcoding. Well how about we game a PUBG and stream it at 1080P highest quality.

    This is the reason why I see x86 vs ARM talk irrelevant and often AT articles are quoted to prove the IPC and all SPEC scores but completely ignore scalability, compatibility, legacy code, HW market etc, when the compute workloads / OS / Software Code / HW which are entirely different world. Like comparing a Jet fighter to a Jet ski.
  • Alistair - Tuesday, December 17, 2019 - link

    Nice rant. Might want to read my comment before going off like a crazy person? I said I only buy Android phones... right there in the first sentence.

    Before you blindly state how amazing x86 CPUs are, as I said, run your Intel CPU in dual core mode at 2.6 Ghz and compare how slow it is vs. the A13 Apple chip that is also 2 power cores at a low frequency. That's what IPC is. I can't understand why people get so triggered about saying Apple has the highest IPC in the industry. It's a simple fact and I just have to assume you don't know what you are talking about. Andrei's articles always seem to attract the most illiterate part of the internet.
  • markol4 - Monday, December 23, 2019 - link

    A13 IPC is superior to Intel or AMD but Apple CPU core is huge in terms of transistors budget. IIRC in A11 times Apple CPU core had at least 2 times more transistors than x86 CPU core. Considering that there is no surprise that Apple has a higher IPC.
  • imaheadcase - Tuesday, December 17, 2019 - link

    They might as well just make a chart and put "BUZZWORDS" on it at this point.

    That is what is so silly about current state of smart phones. So much they can cram into one..but rarely do they do..or if they do its crippled by terrible software.

    Google is already facing so much criticism of Google Photos bullshit, months in and they just say "we are aware of it". lol
  • imaheadcase - Tuesday, December 17, 2019 - link

    I don't think i'll ever understand how Google can take a product, that works great, then release a dozen updates with release notes that "fixes bugs" and completely borks it for users. I mean what is the fucking incentive. Oh and because everything google is so entwined with other software, for whatever reason, it fucks up other things. So now you try to figure out what software is the original culprit or is it the others now. This shit never ends with google.
  • Nicon0s - Wednesday, December 18, 2019 - link

    Do you know what's amusing?
    The vast majority of people reading this article don't really understand what those numbers showed by the SPEC actually mean, what they represent for the functionality of the phone. Most only copy paste things form the article that they like, especially the parts where it's mentioned that the Qualcomm chips are "years" behind. So it doesn't matter how the phone runs and how fast it can execute real world tasks.

    One thing I don't understand is if I would buy a Galaxy S11+ instead of an iphone 11 Pro Max what will I be missing in terms of performance? What specific advantage would the A13 SOC give me because "it's years ahead" in performance?
  • cha0z_ - Friday, December 27, 2019 - link

    My second hand iphone 6s runs super smooth, including in heavy beautiful games - no fps drops or performance issues. Doing so on Galaxy s6 (the available competition model from the same year) is not possible.

    This is where the powerful SOC shines - years down the road where the phone stays relevant and a pleasure to use. Ofc you will not have to worry about that with your S11+ as samsung support their phones fully for only two years (3rd is security updates only). Really they drop the phone as full/serious support even before the first year drops - this is what happened with my note 9, no attention at all - just quick security updates and no interest beyond that. After all - they put the capable engineers to work only towards the new upcoming phones. Apple support FULLY their phones for 5-6 years + they released this summer a security update for iphone 5 and 4s - 2011 and 2012 model. Any android phone from those years receiving a security update?

    Also you can play full PC civilization 6 game on the iphone. No android port and not only because piracy, but because on later turns/bigger maps the android SOCs will choke and the wait time between turns - unbearable. I can list you also a lot more games exclusive to ios, a lot because of performance. Dead cells for example, keeping in touch with the devs - the mobile port dev team (it's outsourced) struggles BIG TIME with performance on android thus massively delaying it.
  • tranceazure1814 - Tuesday, December 17, 2019 - link

    So the main point that I want to know,is it worth upgrading to a Snapdragon 865 over a Snapdragon 855 and while we on the subject does the mi mix 3 5g has less LTE bands than the standard snapdragon 845 mi mix 3?

Log in

Don't have an account? Sign up now