The Snapdragon 865 Performance Preview: Setting the Stage for Flagship Android 2020by Andrei Frumusanu on December 16, 2019 7:30 AM EST
- Posted in
- Cortex A77
- Snapdragon 865
Earlier this month we had the pleasure to attend Qualcomm’s Maui launch event of the new Snapdragon 865 and 765 mobile platforms. The new chipsets promise to bring a lot of new upgrades in terms of performance and features, and undoubtedly will be the silicon upon which the vast majority of 2020 flagship devices will base their designs on. We’ve covered the new improvements and changes of the new chipset in our dedicated launch article, so be sure to read that piece if you’re not yet familiar with the Snapdragon 865.
As has seemingly become a tradition with Qualcomm, following the launch event we’ve been given the opportunity to have some hands-on time with the company’s reference devices, and had the chance to run the phones through our benchmark suite. The QRD865 is a reference phone made by Qualcomm and integrates the new flagship chip. The device offers insight into what we should be expecting from commercial devices in 2020, and today’s piece particularly focuses on the performance improvements of the new generation.
- Qualcomm Announces Snapdragon 865 and 765(G): 5G For All in 2020, All The Details
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- Quick Bytes: Qualcomm’s Dynamic Spectrum Sharing Demo with 5G and 4G
- Quick Bytes: Qualcomm’s Prediction of 1.4 Billion 5G Smartphones by 2022
- Qualcomm Snapdragon Tech Summit Live Blog: Day One
- Qualcomm Snapdragon Tech Summit Live Blog Day Two: All About Mobile
- Qualcomm Snapdragon Tech Summit Day 3 Live Blog: ACPC and XR
A quick recap of the Snapdragon 865 if you haven’t read the more thorough examination of the changes:
|Qualcomm Snapdragon Flagship SoCs 2019-2020|
|CPU||1x Cortex A77
@ 2.84GHz 1x512KB pL2
3x Cortex A77
@ 2.42GHz 3x256KB pL2
4x Cortex A55
@ 1.80GHz 4x128KB pL2
4MB sL3 @ ?MHz
|1x Kryo 485 Gold (A76 derivative)
@ 2.84GHz 1x512KB pL2
3x Kryo 485 Gold (A76 derivative)
@ 2.42GHz 3x256KB pL2
4x Kryo 485 Silver (A55 derivative)
@ 1.80GHz 4x128KB pL2
2MB sL3 @ 1612MHz
|GPU||Adreno 650 @ 587 MHz
|Adreno 640 @ 585 MHz
|DSP / NPU||Hexagon 698
15 TOPS AI
7 TOPS AI
|4x 16-bit CH
@ 2133MHz LPDDR4X / 33.4GB/s
@ 2750MHz LPDDR5 / 44.0GB/s
3MB system level cache
|4x 16-bit CH
@ 1866MHz LPDDR4X 29.9GB/s
3MB system level cache
|ISP/Camera||Dual 14-bit Spectra 480 ISP
64MP ZSL or 2x 25MP ZSL
4K video & 64MP burst capture
|Dual 14-bit Spectra 380 ISP
1x 48MP ZSL or 2x 22MP ZSL
|8K30 / 4K120 10-bit H.265
Dolby Vision, HDR10+, HDR10, HLG
720p960 infinite recording
|4K60 10-bit H.265
HDR10, HDR10+, HLG
(Paired with external X55 only)
(LTE Category 24/22)
DL = 2500 Mbps
7x20MHz CA, 1024-QAM
UL = 316 Mbps
3x20MHz CA, 256-QAM
(5G NR Sub-6 + mmWave)
DL = 7000 Mbps
UL = 3000 Mbps
|Snapdragon X24 LTE
DL = 2000Mbps
7x20MHz CA, 256-QAM, 4x4
UL = 316Mbps
3x20MHz CA, 256-QAM
The Snapdragon 865 is a successor to the Snapdragon 855 last year, and thus represents Qualcomm’s latest flagship chipset offering the newest IP and technologies. On the CPU side, Qualcomm has integrated Arm’s newest Cortex-A77 CPU cores, replacing the A76-based IP from last year. This year Qualcomm has decided against requesting any microarchitectural changes to the IP, so unlike the semi-custom Kryo 485 / A76-based CPUs which had some differing aspects to the design, the new A77 in the Snapdragon 865 represents the default IP configuration that Arm offers.
Clock frequencies and core cache configurations haven’t changed this year – there’s still a single “Prime” A77 CPU core with 512KB cache running at a higher 2.84GHz and three “Performance” or “Gold” cores with reduced 256KB caches at a lower 2.42GHz. The four little cores remain A55s, and also the same cache configuration as well as the 1.8GHz clock. The L3 cache of the CPU cluster has been doubled from 2 to 4MB. In general, Qualcomm’s advertised 25% performance uplift on the CPU side solely comes from the IPC increases of the new A77 cores.
The GPU this year features an updates Adreno 650 design which increases ALU and pixel rendering units by 50%. The end-result in terms of performance is a promised 25% upgrade – it’s likely that the company is running the new block at a lower frequency than what we’ve seen on the Snapdragon 855, although we won’t be able to confirm this until we have access to commercial devices early next year.
A big performance upgrade on the new chip is the quadrupling of the processing power of the new Tensor cores in the Hexagon 698. Qualcomm advertises 15 TOPS throughput for all computing blocks on the SoC and we estimate that the new Tensor cores roughly represent 10 TOPS out of that figure.
In general, the Snapdragon 865 promises to be a very versatile chip and comes with a lot of new improvements – particularly 5G connectivity and new camera capabilities are promised to be the key features of the new SoC. Today’s focus lies solely on the performance of the chip, so let’s move on to our first test results and analysis.
New Memory Controllers & LPDDR5: A Big Improvement
One of the larger changes in the SoC this generation was the integration of a new hybrid LPDDR5 and LPDDR4X memory controller. On the QRD865 device we’ve tested the chip was naturally equipped with the new LP5 standard. Qualcomm was actually downplaying the importance of LP5 itself: the new standard does bring higher memory speeds providing better bandwidth, however latency should be the same, and power efficiency benefits, while there, shouldn’t be overplayed. Nevertheless, Qualcomm did claim they focused more on improving their memory controllers, and this year we’re finally seeing the new chip address some of the weaknesses exhibited by the past two generations; memory latency.
We had criticised Qualcomm’s Snapdragon 845 and 855 for having quite bad memory latency – ever since the company had introduced their system level cache architecture to the designs, this aspect of the memory subsystem had seen some rather mediocre characteristics. There’s been a lot of arguments in regards to how much this actually affected performance, with Qualcomm themselves naturally downplaying the differences. Arm generally notes a 1% performance difference for each 5ns of latency to DRAM, if the differences are big, it can sum up to a noticeable difference.
Looking at the new Snapdragon 865, the first thing that pops up when comparing the two latency charts is the doubled L3 cache of the new chip. It’s to be noted that it does look that there’s still some sort of logical partitioning going on and 512KB of the cache may be dedicated to the little cores, as random-access latencies start going up at 1.5MB for the S855 and 3.5MB for the S865.
Further down in the deeper memory regions, we’re seeing some very big changes in latency. Qualcomm has been able to shave off around 35ns in the full random-access test, and we’re estimating that the structural latency of the chip now falls in at ~109ns – a 20ns improvements over its predecessor. While it’s a very good improvements in itself, it’s still a slightly behind the designs of HiSilicon, Apple and Samsung. So, while Qualcomm still is the last of the bunch in regards to its memory subsystem, it’s no longer trailing behind by such a large margin. Keep in mind the results of the Kirin 990 here as we go into more detailed analysis of memory-intensive workloads in SPEC on the next page.
Furthermore, what’s very interesting about Qualcomm’s results in the DRAM region is the behaviour of the TLB+CLR Trash test. This test is always hitting the same cache-line within a page across different, forcing a cache line replacement. The oddity here is that the Snapdragon 865 here behaves very differently to the 855, with the results showcasing a separate “step” in the results between 4MB and ~32MB. This result is more of an artefact of the test only hitting a single cache line per page rather than the chip actually having some sort of 32MB hidden cache. My theory is that Qualcomm has done some sort of optimisation to the cache-line replacement policy at the memory controller level, and instead the test hitting DRAM, it’s actually residing at on the SLC cache. It’s a very interesting result and so far, it’s the first and only chipset to exhibit such behaviour. If it’s indeed the SLC, the latency would fall in at around 25-35ns, with the non-uniform latency likely being a result of the four cache slices dedicated to the four memory controllers.
Overall, it looks like Qualcomm has made rather big changes to the memory subsystem this year, and we’re looking forward to see the impact on performance.
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iphonebestgamephone - Tuesday, December 31, 2019 - link"I am into android from the start + symbian before than and also senior member with dev/helping known devs with project @ xda. So thank you, I know enough about android." Haha... I should have known you would come up with something like that.
"Btw, used android for 10 years (only high end phones) till I switched to the pro max + I have highly technical background as education, hobby and work - especially in the field of electronics and computers" this one too lol.
And then you somehow decide civ6 and deadcells dont run cus android too weak. No. Its just the devs dont bother with it. They could have restricted it to atleast sd820 devices like what grid autosport devs are doing.
"Emulation is cool, did a lot on android with it. Including fun stuff like running diablo 2 LOD latest patch on my note 9, believe me - it's playable with the spen when on the go, in home one mouse and the TV = you are good to go. Still, ported or developed games for mobile just works better and you have such a vast library nowdays with high quality games that you really don't need to revisit old classics on your phone. Actually on ios the situation is a lot better, you got a lot more paid apps there vs android." Im yet to find some good stuff like god of war, nfs, burnout, wipeout, xenoblade, pokemon, zelda or mario, on android, or any other thousands of games. You could say you can stream them, but same goes for pc games too. Emulators and a switch style gamepad is great on the go. I see apple has done a great job with metal, vulkan is worse than opengl on android 10 sd855. Looking forward to the updatable drivers on the 865.
"I can play fortnite maxed at 60fps and no fps drops or whatever even after 2 hours of play without major heating and you are talking about PUBG maxed. :)"
Thats awesome, sd855 heats up a lot on pubg maxed. I guess there is no pubg gfxtool for ios.
cha0z_ - Thursday, January 2, 2020 - linkThere are emulators for ios and you don't need jailbreak to install/play games. They are not on the app store tho, they are on custom stores - still, it's not any different than installing APK from outside playstore. The emulators library is quite big, including ppsspp. As I said tho - android is better for emulators imho + I didn't say android is weak as OS. Weak are the SOCs on android phones compared to the A series of apple. I would totally love to see android phone with apple SOC/similar performance to it and longer full support than two years.
As for the gfxtool, I hope you understand that when you have literally just a few phones to optimise for - you really do a great job with it, or with other words - the ios pubg variant is greatly optimised for every iphone that supports it to extract the best experience with the best possible gfx for the hardware. Ofc you can argue than personal preferences can apply and tweaking can be done, but it's not that necessary.
I respect your opinion and share few viewpoints, just from personal experience - gaming on ios is generally better. Hard to explain, games run smoother and better. If you love emulators tho - android is obviously a better choice + snapdragon SOC.
iphonebestgamephone - Tuesday, January 7, 2020 - link"Weak are the SOCs on android phones compared to the A series of apple." Yeah everyone knows. They still are strong enough for the games you mentioned though, atleast the last 2 years of flagships. And last years 730/730g are also good enough. I guess the devs want even those with 100$ phones play their games. I doubt those people would even bother buying the game once it hits the store.
Gamebench did a test and the huawei mate 30 pro actually performed better than the iphone 11 pro amd note 10 in games. https://blog.gamebench.net/huawei-mate-30-pro-ipho...
The iphone probably had better visual settings/higher resolution as default probably.
Ahmedrr1 - Sunday, December 22, 2019 - linkNice
AceMcLoud - Sunday, December 22, 2019 - linkOuch, that doesn't look very promising.
ballsystemlord - Friday, February 7, 2020 - linkSpelling error:
"The test here is mostly sensible to the performance scaling of the A55 cores. The QRD865 in the default more is more conservative than some existing S855 devices,"
"mode" not "more":
"The test here is mostly sensible to the performance scaling of the A55 cores. The QRD865 in the default mode is more conservative than some existing S855 devices,"
Hrel - Tuesday, April 28, 2020 - linkMan these Watt listings make no sense at all.
5.12 Watts is shows as lower than 4.24 Watts then 2.73W is somehow HIGHER than that?! WTF is going on?
Then 3.33W is higher than 2.73, which makes sense, but then 3.05W is lower than 2.56W?! What are these charts?
Hrel - Tuesday, April 28, 2020 - linkOh, the bar is for the Joules, the Watts aren't visually represented. Runtime being a critical variable, I gotcha now. Lol, I was so confused :)