yashsingh1/xdaforums huggingface dataset:
[Nexus 6  General] SMARTPHONEPC:
So do the following comments at those videos have merit or not, I assume the Nexus 5 running the same software (i.e. running Android L with encryption enabled) does not have a dedicated encryption chip so is it slower memory storage hardware in Nexus 6 or a software driver issue specific to Nexus 6 hardware that will be fixed?

Google dogfooding & Motorola never catch this or is the Nexus 6 still a beta device not ready for final release & another reason for delays of full launch?

Hopefully encryption will work on Nexus 6 with no performance hit as reported here on the Nexus 5 running Android L with encryption enabled asap (why would Motorola bottleneck the Nexus 6 with cheap bad performing memory when it sells to tech enthusiasts who would notice-did reviews test this) ..

Maxime Caudebec22 hours ago

nope, because Google was too lazy to put a dedicated encryption chip like Apple so the NAND R/W speeds are pathetically slow﻿

Aldin Shata2 hours ago

Nexus 6 has very slow read/write flash speeds compared to the competition, thats why it is slow, it launches applications just as fast as a Nexus 4 , which is over 2 years old already...the Nexus 5 and the competition load applications and games noticeably faster (like the Note 4, Moto X 2014, HTC M8, 6/6 Plus, etc)

They are saying that it is Google's poor implementation of disk encryption in Lollipop(it is standard now in Lollipop) that causes this, or it could just be Motorola and Google gimping out on good quality memory storage..﻿
[Nexus 6  General] gtg465x:
But some people are saying the Nexus 5 gets super slow and laggy when you enable encryption in Lollipop, so I'm not sure it's crappy NAND in the N6.
[Nexus 6  General] maxesxp:
Unfortunately, I think the spells out the Nexus 6 getting absolutely destroyed in the "PhoneBuff style speed tests" :(
[Nexus 6  General] SMARTPHONEPC:
I was referencing:

According to description at https://www.youtube.com/watch?v=cqTNTojlwwg encryption on Nexus 5 with Android L added 14 seconds to the boot time (49 sec vs 35 sec, I'd prefer less of a difference but not convinced-sure it's a deal breaker at this point or if it will get worse over time with more data or better with software updates as the Nexus 6 reportedly does not have hardware encryption like the iPhone 6):

"Boot times:

Nexus 5 unencrypted: 35 seconds

Nexus 5 encrypted: 49 seconds"

[YOUTUBE]watch?v=cqTNTojlwwg&feature=youtu.be[/YOUTUBE]
[Nexus 6  General] ECrispy:
It's pretty simple really. Full disk encryption as done by Google is inefficient and slow because :-

1. the data is read by cpu from flash and then written to memory. Thats 2x reads/writes and using slower main memory bus. Vs Apple using a dedicated memory controller that uses optimized signal path and only needs to encrypt/decrypt data while it reads/writes it. Data has to flow thru memory controller anyway so there are no extra reads/writes.

2. the SoC lacks ARM v8 so there are no hw accelerated AES instructions and things are done in software using cpu cycles and battery.

3. It is possible the NAND is of lower quality and just has slower speeds

#1 is not fixable, its just bad design

#2 is also not fixable, it needs ARM v8 cpu

I'm willing to bet HTC and Samsung phones coming out next will include both of these fixes. The software fix is to disable encryption which will need a custom kernel and is not good as it defeats the whole point of encryption which make your data more secure. There is no real fix.

And if #3 is true then it really doesn't matter much anyway. And btw, FDE with proper hw support (like on iPhone or any pc) barely adds any time and is not even noticeable. Its a great feature when implemented properly.
[Nexus 6  General] SMARTPHONEPC:
How certain are you about that because if so it won't be fixable on the Nexus 6? I agree that sounds like a bad design & should have been done with hardware encryption as Apple-PCs manage to do it without performance hits & extra read-writes-straining memory. I want encryption so I may tolerate it or reconsider Note4 if it proves a significant issue or consider a Nexus 6 more as a secondary handset device..
[Nexus 6  General] ECrispy:
I'm not going to make excuses for Google - the Nexus 6 and L have both been released and we should review them today, and there are no fixes I can think of. I know people will say 'software update will fix this' but that's just a wild hope with no real basis.
[Nexus 6  General] jkc120:
I really hope Google can identify some non-optimal code to fix so that we don't need to disable encryption. But with CM stating they'll also require encryption, I guess CM is out if you want to avoid the crappy performance.

Guess I'll use the N6 for a week or so and see if it's noticeable/annoying and return it if so, but this is really disappointing and IMHO a big oversight on Google's part.
[Nexus 6  General] SMARTPHONEPC:
Assuming the encryption hardware is not there & is responsible for the encryption performance hit, what are the chances:

1) Google allows disabling Full Disk Encryption & instead enabling encryption on a non-boot partition?

2) A developer does #1

Is this encryption performance Nexus 6 issue a deal-breaker for you or others?
[Nexus 6  General] ECrispy:
I'll see when I try the phone in store for myself. But already from videos and reviews we know that app launch, boot times are affected. I can't really say without using if its going to bother me or not. But if games run slowly on the phone, with its amazing gpu that will then go to waste, then what's the point?
[Nexus 6  General] jkc120:
I guess the point is "enterprise". But I don't see why they didn't have a way to disable it somehow. Surely they could have found a way to make it option, and failing that they should have planned for dedicated HW to offload the crypto.
[Nexus 6  General] Droideez:
Good info here thanks..

My question is will Google acknowledge anytime soon to explain?
[Nexus 6  General] jhax01:
That seems unlikely to me... I'm a Google fanboi but they are no different than crApple in this regard... They will probably tell you it's actually fast if you hold it the right way...lol
[Nexus 6  General] Dr Faustus:
I have a question (and forgive me if this was already answered) but does encryption also add difficulty for modifications to be done to the stock Android OS?

Just trying to figure out if it is something I should consider disabling when rooting the N6 (and prepare for custom mods in due time).
[Nexus 6  General] phekno:
I'm 99% sure the Snapdragon 805 (Krait 450) has a hardware crypto module built in. According to this the hardware crypto module is FIPS 140-2 certified and it specifically mentions full disk encryption and Android.

Also, anecdotally, I enabled encryption on my N5 running the factory Lollipop image (not the developer preview, which I thought ran pretty slowly) and I don't think there's a noticeable difference between it running with it on or off. Honestly, I didn't time it when it booted up, because I personally couldn't care less about how quickly it boots up, given that I very rarely reboot it.
[Nexus 6  General] open1your1eyes0:
Only outside of the OS (like recovery and such). If you're booted into the OS and unlocked the PIN then you're good as it decrypts in real-time.
[Nexus 6  General] jkc120:
If that's the case, hopefully it's not yet enabled and isn't using the dedicated HW, because I was hoping the jitter/lag mentioned in the reviews fairly across the board were due to this, and that we'd have a fix. Plus the really slow boot/app loading time. I'll be disabling it the first reliable way, that's for sure.
[Nexus 6  General] ttabbal:
Considering that the Note4 has the same SOC and encryption doesn't seem to bog it down as much, I think it's quite likely that Google cut a corner and just didn't use it. And an older Note3 in my hand right now also runs just fine encrypted. I can't tell the difference. I haven't run benchmarks as I don't care what they say. Too many variables to get reliable benchmarking on Android. What matters to me is how it performs in every day use. And it works great.

The trick is going to be figuring out how to use the hardware crypto engine as Qualcom isn't well known for being friendly with such things. It should be as simple as a call to set the key and calls for encrypt/decrypt. Perhaps we can use the kernel source from the Note4 to figure it out.

Personally, I'm not very interested in the device until this is fixed. The biggest reason I wanted to move to it was software performance, Google crippled that. It's quite likely it can be fixed in software, but my money doesn't get spent on maybe. It's not a big upgrade, hardware wise, from my Note3, so I can wait. And no, disabling encryption is not a fix. If my old Note3 can do it, there's no excuse for a flagship Nexus not to, particularly at this price level.
[Nexus 6  General] jkc120:
I don't see how you can judge yet as you haven't held a N6 and compared it with and without encryption. And you're also not comparing apples and apples with the Note 4 on KK and the N6 on lollipop. For all we know, the Note4 has the acceleration enabled and the N6 with lollipop doesn't for some reason. Additionally, I don't think the encryption on the Note is the full device is it? Again, not apples to apples.
[Nexus 6  General] ttabbal:
Close enough for my taste. As I would need to get the 64GB version, I can't even compare them in store. I'll check them out when demo units hit the TMobile stores. But seriously, Google has been shouting about how ART/L is supposed to make the experience so much better. Then gets smoked by a KK/Twiz device with the same hardware specs? Fail. And unencrypted performance is irrelevant to me, as I won't run without encryption.

Now, it is fair to point out that on the Note3, the system partition is not encrypted. Just the main storage at /data. Does the L encryption do /system as well? It probably should just to keep out possible attack vectors. But still, a debloated Twiz weighs in at 1.5GB or so, AOSP at about 300MB, add another 200MB or so for Gapps to make things about equal... That does slow things down. Running an AOSP KK on the N3, you can really feel the difference in performance. Sadly, the last time I tried them, they got unstable after a few weeks. I'll probably try the latest ones again just out of curiosity. And for performance, /data is very important. After boot, most I/O is there. So again, close enough.

I'm not writing it off entirely, but I went from very likely to order as soon as the order pages go live to waiting to see how things shake out with devs and Google making changes. And it's just my needs/desires. Everyone else has to make their own decisions. And I do think it's very fixable, the SOC has the ability, but it's likely not being used. If it IS being used, something worse is going on, likely poor performing flash chips. If that's the case, there's no way I'd buy one. I think that's unlikely, but I'm not willing to find out after dropping $700.
[Nexus 6  General] jkc120:
Yes my understanding is that everything is encrypted. I'm not sure if they're doing it at the device level or partition level (and doing all partitions) or what, I honestly haven't looked into the details. I just know it's more exhaustive in lollipop on the N6.

We really won't know until someone gets one and manages to flash a workaround similar to what the Nexus 9 has and compare things with and without encryption. Once we have Nexus 6 devices shipping to the masses, we need to create an issue and star the hell out of it to get them to ACK it and do something about it, either via a workaround to remove encryption or by enabling the needed HW support.
[Nexus 6  General] Bucky Barnes:
Perhaps Google avoided using HW encryption to keep everything open sourced. IIRC, the Nexus 5 lacked several optimizations for the same reason.
[Nexus 6  General] jkc120:
For a company that makes so much damn money, they sure are stupid at times. "Hey guys, let's force whole-device encryption, but not enable the hardware that supports it, what could go wrong??"
[Nexus 6  General] doitright:
Wow, slow boot.

And this matters because.... why exactly?

If you have to reboot it more than once every few MONTHS, then you're doing something wrong.
[Nexus 6  General] jkc120:
Obviously. Does opening apps matter to you? Because it's markedly slower at opening apps and multitasking if it has to go to the flash memory (disk). There are side by side videos showing the Nexus5 being more responsive than the Nexus 6. Does THAT matter to you? Sorry, but if the device feels overall slower than a year old device, they're doing something it wrong.
[Nexus 6  General] doitright:
This is entirely meaningless.

ARM v8 is NOT required for hardware cryptographic acceleration. In fact, snapdragon 805 HAS a hardware cryptography accelerator.

https://www.qualcomm.com/news/snapd...ic-module-snapdragon-805-fips-140-2-certified

*** which is not to say that Google is actually USING it -- only that it is PRESENT.

It is far more likely, that the builds of Android 5 being evaluated were PRERELEASE, and that Nexus 6 will gain the SAME performance improvements that benefited the Nexus 9 as of, I think, yesterday.

There is nothing there TO fix.

Nonsense, as explained above.

Meaningless, since it ignores reality.

#3 is very unlikely.
[Nexus 6  General] evocalante:
My friend who works at Tmobile just showed me his demo unit and it was super snappy, loud front speakers, and the front facing speakers were loud. Who cares about benchmarks.
[Nexus 6  General] doitright:
0%

100%

As in, its already been done.

Also FYI: Only the USERDATA partition is actually encrypted. The system partition is not.
[Nexus 6  General] jkc120:
Again, I will reserve final judgement until I have it in my hand to test, and I agree that benchmarks are meaningless. However, if it takes longer for the N6 to open apps and multi-task than the N5, then something is wrong. If you force something on the end user, it should be transparent. Being slower than last year's device with a newer SOC and faster RAM and (I would hope) on-par NAND is unacceptable. That said, for me since I'm coming from a Galaxy S4, if it's faster than that I guess personally for me it's still an upgrade so *shrug*
[Nexus 6  General] doitright:
They *did* provide a way to disable it.

fastboot oem unlock

fastboot flash boot boot-with-encryption-changed-to-optional.img
[Nexus 6  General] jkc120:
"They" being NOT Google. Google should have given an option to disable it somehow. Personally I have no qualms with doing it myself.

And since CM is "forcing" encryption, they may not even install if you're not encrypted. Which really sucks.
[Nexus 6  General] doitright:
No. Encryption is based on a flag passed to vold through the fstab file, and applies specifically to the USERDATA partition, not the system partition.

---------- Post added at 06:58 PM ---------- Previous post was at 06:56 PM ----------

Starting applications is a different topic. I was addressing specific complaint about increased boot time.

---------- Post added at 07:00 PM ---------- Previous post was at 06:58 PM ----------

They **BEING** google, who you can THANK for selling you hardware that is firmware unlocked, and for the source code necessary to make this very trivial change.
[Nexus 6  General] jkc120:
That's a nonsense argument. If it's not simple enough for an average user (which you know even fastboot oem unlock is too hard for, hence these stupid "kits" to do it), then it's not relevant.
[Nexus 6  General] gtg465x:
To be fair, every device out there still feels slower than the Nexus 5 to me. It's a beast, still. The One M8 and Moto X 2014 feel about as fast as the N5, but they don't feel faster. The S5, Note 4, G3, OnePlus One, Galaxy Alpha, Droid Turbo, and Sony Z3C all feel slower than the Nexus 5, yet all are newer And have better specs. I think QHD devices need a Snapdragon 810 to be faster in day to day use than a 1080p device with a Snapdragon 800/801.
[Nexus 6  General] jkc120:
Neither the M8 nor the 2014 MotoX have a SD805, nor the faster RAM. I don't know why people make excuses for Google like this. If Samsung released the Galaxy S6 and it was slower than the S5, they would get reamed. But when Google does it, it's all ok. SMH.
[Nexus 6  General] hotleadsingerguy:
Sorry? I have 3 computers and a laptop in my house, all run 2560x1440, and all have faster than 3Ghz quad-cores.

My work computer even runs a core i7 extreme at 3.8Ghz.

I think you're a few years behind, in the computer market.
[Nexus 6  General] gtg465x:
Note 4 and Droid Turbo both have a Snapdragon 805 and both feel slower than the Nexus 5. Sorry, but the Snapdragon 805 cannot drive a QHD display faster than a Snapdragon 800/801 can drive a 1080p display. At best it can match the speed. We need Snapdragon 810 to make devices with QHD screens truly feel faster than older devices with 1080p screens.
[Nexus 6  General] ECrispy:
Excuses are always made for a Nexus. Except this time its $650 phone and 350, there is absolutely no room for excuses. I don't really know what the deal is with encryption, but something is going on and I very much doubt Google is going to come out with an explanation. If its a software issue, why did they release buggy/unfinished code?
[Nexus 6  General] jkc120:
Riddle me this: How exactly is the display mattering when opening an app? Hint: it doesn't matter. What you're talking about is the smoothness, which I agree is probably slightly worse due to the QHD display. However, the display has nothing to do with how quickly an app opens. It's not as if the extra time is spent in drawing the screen for the app, it's just not able to read the app from the NAND as quickly.
[Nexus 6  General] gtg465x:
Yes, I understand that the Nexus 6 feels slower because of encryption slowing down NAND reads and writes. What I'm saying is, even without encryption, I don't think the Nexus 6 will feel faster than the Nexus 5. At best, it will feel the same. The Snapdragon 805 is barely capable of pushing a QHD display as fast as the 801 could push a 1080p display, so if encryption is enabled, of course the Nexus 6 will feel slower than an unencrypted N5. But that's an Apples to oranges comparison. Encrypt the N5 and guess what, the N6 is no longer slower. They will be the same.
[Nexus 6  General] jkc120:
Understood, then we're in agreement across the board :)
[Nexus 6  General] Illrigger:
After reading through this thread, I'm going to go ahead and say that this is the single most salient point made here. Android 5.0 is still cooking, that much is very clear. The Material version of Chrome and Google search just now came out, and more apps that are optimized for 5.0 are coming every day. We'll likely be seeing new builds out of Google in the very near future that will speed things up, optimizing the OS for the hardware on the device and for the new versions of the apps.

Is that a good excuse for why the phones are shipping before the OS is really ready? No. However, going ballistic over launch numbers for the N6 is definitely premature. If you aren't impressed with the numbers, fine, don't buy one yet - but I would reserve final judgement for a couple months down the road when things are smoothed out. Personally, I'm still getting one. Worst case, I Jump to something else in 6 months. I would probably do that anyway.
[Nexus 6  General] TheSopranos16:
I have one preordered and am very concerned with this performance issue. I read most of this thread and many have pointed out that its possible to reflash the build with the encryption flag off. Are there any reviewers out there with a unit to try this on and then compare storage benchmarks and boot time?
[Nexus 6  General] nexus6R3plicant:
Probably not but go read through the n9 threads they are doing it to turn encryption off
[Nexus 6  General] italia0101:
What's a little worrying is the nexus 9 even with encryption shows significantly higher read speeds

Nexus 9 Encrypted * * * * * *- 286 MB/s

Nexus 9 Unencrypted ( via custom rom ) * * * * * * * * * * * * * * * * * * * * -353.86 MB/s

Nexus 6 Encrypted * * * * * *-60.87 MB/s
[Nexus 6  General] JManekia:
Maybe a 64 bit processor is the cure
[Nexus 6  General] jkc120:
Ouch. I guess we'll find out once someone has an N6 and is willing to do this comparison (making an image without the forceencryption sounds trivial). If it's really low-quality NAND, I'll be returning my Nexux 6. If Google/Moto think they can sell a $650 phone with a huge bottleneck (i.e. crappy NAND), then they are not getting my money.

---------- Post added at 02:43 PM ---------- Previous post was at 02:42 PM ----------

No way is that a factor.
[Nexus 6  General] jcarlm:
Checked out a demo at T-Mobile today. It booted up pretty fast.
[Nexus 6  General] benburch9:
i think it's looking increasingly clear that low quality flash is not the problem. I mean, come on. What are the chances that they really used flash that's 1/5th as fast as everyone else and way slower than the previous nexus. It's far far far more likely that this is an issue with software, probably that encryption is not being handled correctly.

I wouldn't take nexus 9 performance to mean anything. The nexus 9 has a different CPU and is likely using ARMv8 AES instructions. Google needs to do something totally different for the nexus 6 (i.e. use Qualcom's acceleration).
[Nexus 6  General] italia0101:
Performance feel good ?
[Nexus 6  General] jcarlm:
It didn't get to run it hard. It wasn't even connect to WiFi or service. But it was smooth for me.
[Nexus 6  General] sailindawg:
Interesting thread, but several things bothered me about the Arstechnica review. No where's did he mention his OS build. A few reviews stated that they could not review the phone until they recieved a certain update. The review phones were issued with unfinished firmware.

Secondly, encryption can will cause slow downs. Encryption needs to be optimised. It's the first time Google has put it into an OS full time as part of the OS.

lastly, when is a Nexus device ever a "finalized" OS. It's continually updated, changed by Google. Some updates better than others. Hopefully it's gets resolved with an OS update. I find it interesting that only ARS find this. I am beginning to question the validity of a lot of these review sites after so many years reading them. I value this forum's readers experiences more.
[Nexus 6  General] digesh9870:
Where and when could I find a final verdict on this ? Would like to see a review from a person who has actually used a non-review unit for a couple of days and with latest software ? Can't trust benchmarks since most of them are not capable of running well on lollipop. Regarding sequential read/write speed with encryption, is it that all apps and games launches slowly or is it that only large sized apps/games are affected and are noticeable for the slower launch? Is it really a hardware issue or a just a software bug that might soon be fixed by Google with an update ? Thanks.
[Nexus 6  General] Illrigger:
So few people actually have the devices in hand at this point that we don't know. By the end of the day on Wednesday that will have changed, but even then we really won't know much until Google has pushed out the inevitable 5.0x updates to the OS with all the fixes for issues we are likely to uncover as well as fix performance issues. This isn't something we will know the answer to overnight.
[Nexus 6  General] htowngator:
My lg G3 is encrypted for work and the boot time is horrible compared to not encrypted when I first got it.
[Nexus 6  General] Dr Faustus:
'Tis great, mate! :D