yashsingh1/xdaforums huggingface dataset:
[Nexus 9 General] oediv:
Nexus 9 32 GB lte

1. Run 6:45

2. Run 7:15

3. Run 7:00 but with a runtime from 36 hours since the last Charge

Let's test the next Run with faux kernel :)
[Nexus 9 General] Semantics:
My 3rd charge has been good. Taken off the charger at 11pm on the 26th, I have 7:30 mins screen on time and 27% battery left. I've only been reading a book and browsing the web but I'm satisfied with 3 days off the charger and by the time I charge it probably 9 hours of SoT.
[Nexus 9 General] JXulo:
Yes you can reach 9 hours if you use it more for reading books. If you use it more for browsing you will be luck with 5 hours.
[Nexus 9 General] Semantics:
I use it mostly to read comics and Google books, so it should serve me well. I also use it for work purposes, documents, etc. Should meet my needs quite well, and its a superior format for e-reading. I'm not really a tablet gamer, my PC spoils me.
[Nexus 9 General] R3Lax1:
No, I easily reach 7 hours only in chrome.
[Nexus 9 General] JXulo:
Stock? Can you put prints here please? I think you are the first one here in xda with such a good values in Chrome!

My personal best was 5 hours but my average is around 4:30. Today for example, 25% remmaining battery with 4:12h of screen. I have it for a week and 90/95% of the time is browsing and the results are very consistent with other members have showed here...I use the brightness 25%+\-.
[Nexus 9 General] USBhost:
Here

http://xdaforums.com/showpost.php?p=56947615&postcount=202

I was on chrome all that almost 8h
[Nexus 9 General] JXulo:
Wow. But you don't answer, is that on stock? If yes then very good indeed!

I just can't pass 5 hours no matter what, just browsing with brightness 25+/-. If i have values like yours i would be happy but unfortunately i haven't, not even close.

Edit- OK you are not the same person from yesterday lol (my mistake) and you are with different kernel etc etc etc.
[Nexus 9 General] Chyeo1979:
8hrs on chrome is really a fantasy and wetdream! Will the stock software ever be optimised to reach that mark?
[Nexus 9 General] Rebecca James:
44% after 6 hours :)
[Nexus 9 General] jd1639:
I'll just drop these here. Stock rom and kernel.
[Nexus 9 General] USBhost:
maybe when google fixes that cpu governor
[Nexus 9 General] blakeslee14:
A little better on the second full charge.
[Nexus 9 General] JackHanAnLG:
Pretty disappointed tbh

This was with brightness on 0-50% no game usage apart from the last 10%

J
[Nexus 9 General] JackHanAnLG:
Apparently my battery is worse then a nexus 4....
[Nexus 9 General] jd1639:
What is that?
[Nexus 9 General] ÜBER™:
I get this pretty consistently, an hour worth of gaming on CoC and watching some movies among other things. Almost 2 days and 7hrs SoT. I can dig it :).

http://imgur.com/ywk4QaK

http://imgur.com/KQfQUsU
[Nexus 9 General] cwepruk:
I'm struggling to get 5 hours. I'm very unimpressed considering all the reviews I've read show almost 10 hours for browsing, and those are supposed to be actual tests.

I'm pretty much just surfing the web and checking twitter. Chrome destroys my battery, but Dolphin isn't doing much better.

I'm at 3.5 hours SOT with 25% left. That's bad anyways you slice it. Brightness is turned down as well.
[Nexus 9 General] serial_carpens:
I was getting about 4.5 hours screen on time with chrome browsing. Then i ran a factory reset and turned off location and hotword detection. Battery life now is drastically better. I was at around 4.5 hours screen on time with 40% battery left last night.
[Nexus 9 General] drucquerkellan:
I'm on an LTE Nexus 9 32 GB:

Getting 6-7 hours screen on time pretty consistently, LTE or WiFi. I keep my brightness at about 80%.

I'm currently sitting at 25%. I mainly play CoC, take online Udemy courses, watch videos/movies, do some web browsing, and homework. The thing I noticed for the first few days was it would take forever to charge. I would plug it in at night and wake up in the morning after 7 hours of sleep with it at 60%. I think it's starting to straighten itself out after some power cycling though.
[Nexus 9 General] di11igaf:
Was that stock cpu clock speed or under clocked?
[Nexus 9 General] USBhost:
Stock speed with modified cpu gov
[Nexus 9 General] srv1973:
Usage under idle...

Hi all,

Got my Nexus 9 32BG White last Saturday. Had about 85% charge yesterday at 19:00, used the tablet for about 45 minutes just doing web browsing and then put it down. Woke up this morning with 30% charge left. This was after the first charge cycle (which went only up to 85% cos I was charging in the office and had to leave for home, and I was charging off my laptop USB port btw). That looks really bad to me...

[edit] GSam shows 43% for Android System and 30.6% for Kernel under App Usage... now that makes sense I suppose if I'm not using any other apps at all, cos they'd take up a proportionally larger part of CPU time... Android battery stats show 7% for OS and 6% for system, nothing else exceeds3%.

Is this similar to what others are seeing?
[Nexus 9 General] milkaCH:
I just ordered mine but I want to share some experience done with Lollipop battery life.

I just encountered some strange bugs with my HTC M7 GPE with Lollipop and I think that all these battery issues are coming from localisation bugs with Google v5. I just had some bad experiences where localisation icon into notification bar was spamming (very strange) constantly for hours draining all battery and warm a lot my device.

First I had a very bad battery life on my device. Then, after a factory reset and disabled all localisation extra settings, the batttery life was again normal.

Now, this bug can appear if I don't close some application (surely not correctly coded according to new Lollipop API or creating some issues with it).

I definitively don't think that these issues are related to hardware defect but only due to some issues into Lollipop.
[Nexus 9 General] .vermilion:
Some people reported a bad/broken charging-cable. I suggest you to try another cable and see if it's still charging that slow!

Sent from my Nexus 9
[Nexus 9 General] srv1973:
Charged to 100% yesterday afternoon, did a small amount of browsing (around 30 minutes) around 21:00, then again around 30 minutes between 22:00-22:30, the battery was at 65% then. Put it away. This morning it was at 45%. Browsed for 15 minutes around 07:15, put it down. Picked it up again now (12:50) and it's at 35%. Looking at the battery stats (history details) I can see a steady decline in charge from 18:00 yesterday to 07:00 this morning, then a very sharp decline just after 07:00 and relatively flat from then on. I really wonder why I get such a decline in charge overnight...
[Nexus 9 General] laill:
My own stats

Have be using N9 since the launch, I think the stats is just fine for me.

System is 22C, with ElementalX kernel, twisted some options.

(2 out of 4 hours were with loudspeakers playing music loudly:rolleyes:, Wi-Fi on all the times with regular g+ photo auto-backup and Titanium scheduled backup)
[Nexus 9 General] Chyeo1979:
Seemed like web browsing is still the main battery killer, even more than when playing many of the games.

Those with 4 - 5 hrs SOT are usually heavy users of web browser while those with longer SOT seem to do quite some different tasks with it.

Any experts know why? Never had the impression that web browsing is the main battery drainer before started using Nexus 9.
[Nexus 9 General] Nidstang:
This is my view as well. I've been using my 9 for a couple of months pretty heavily, and this has been my experience. Standby time (with WiFi on or off) is very good, and using it with Tapatalk, games, and work-related apps all yield good battery life. Web browsing (Chrome) has a disproportionate impact on battery life -- though it has gotten a little better since I bought it (due, I guess, to the recent Chrome updates and/or the update to 5.0.1).

Interestingly, I am a big user of this app. At first, it caused battery drain as bad as or possibly worse than Chrome. The dev updated it with "Support for Android 5.0, Lollipop" and the battery drain problem immediately went away.

Does anyone know if other 5.0.x devices are seeing battery issues when web browsing?
[Nexus 9 General] srv1973:
Sigh, and again. Started yesterday around 20:00 with 95% charge, used the tablet for an hour or so doing web browsing, press reader, aquamail and e-book reading, then I rebooted the tablet and put it down for the night. brightness is at around 20% btw. I can see in battery history a steady and steep decline of charge during the night, at 07:30 I had 40% charge left. That's a 30% drop from when I put the thing to sleep, completely idle. Strangely enough, once I left the house (I carry it with me to the office every day) the decline has been minimal (~4% in 3 hours)!

At home I'm on a wireless AC network, in the office on wireless N. I haven't used it in the office yet, it's just been sleeping next to me.

According to GSam, since I last unplugged the tablet the screen used 28%, apps 68%. App usage has 23.5% Android Kernel, 15.4% Android System, 15% AquaMail (need to investigate this! seems high considering how little I accessed AquaMail), 3.6% Google Play Services and 2.2% Press reader. The rest is all >= 1%. This is starting to annoy me. Any tips on how I can fix this? I starting to think there's something wrong with wireless AC power usage?
[Nexus 9 General] tu3218:
I will say that a factory reset has definitely increased my battery life. All the same apps installed that were on it before.
[Nexus 9 General] seanashmore:
Bizarrely mine has stopprd heating up as much and my batterry life drastically improved after a cache wipe on stock 5.0.1.

Battery currently at 29%, with 5h SOT. Played game dev story for about an hour now and the tablet says i have approx 14 hrs total time left. I would imagine ill get another hour or two SOT which im thrilled about because up until now i have had heat issues and terrible battery life.

I would attribute the change to the cache wipe and having done a few full battery cycles now i guess.
[Nexus 9 General] borchgrevink:
Cache wipe how?
[Nexus 9 General] ElementalXY:
go into recovery mode then you'll find wipe cache. It will take about 10 minutes until the wiping is done then you can reboot the system afterwards.
[Nexus 9 General] cr0wnest:
I just got my Nexus 9 few days ago, and the battery life is kinda disappointing. I've got 2hrs 30mins of screen on time, and im already down to 44%.

Granted, the deep sleep idle drain is reasonably low, but as long as the screen is on, I think the battery life is worse than my Xperia Z2. How'd you guys get such high SOT? I just did the cache wipe so I'll continue to monitor it from here on.
[Nexus 9 General] nullzwo11:
The question is, what are u using your n9 for?
[Nexus 9 General] KingMarkous:
battery life doesn't seem impressive really.
[Nexus 9 General] seanashmore:
Honestly my N9 took from Christmas day until around last week sometime to really start giving me decent battery life, I have no idea why, maybe some sort of battery cycling business or something similar; the overheating issue seemed to stop as well which I would imagine contributed to it. Granted some days I do a lot of book reading rather than game playing but I do also spend a good hour or two gaming some days.
[Nexus 9 General] madsquabbles:
mine is just a small sample of 1hr pretty much out the box - but i got 10% drain in that hour surfing - watching webm's and h264 vids, lotsa refreshing. 0% brightness. 10 hours of surfing (if it holds up) seems pretty good to me. no sound also, i think i read that the headphone amp draws a little over 1 Watt max.
[Nexus 9 General] JXulo:
If you use nexus 9 mostly for broswing you can get 4:30/5:00 hours. If you use an adblock you can squezze more 45 minutes or even one hour and get almost 6 hours if you drain the battery to zero. If you use it for reading pdf's or/and watch movies you should get about 9 or 10 hours.

My advice to you is to read this thread carefuly, it's all explained if you correctly interpretate the values. But i can resume a little, those high SOT aren't in stock kernel/rom and/or not using broswer a lot. For some reason chrome (and other browsers) drain the battery very fast.

I already return mine because i browsing a lot and almost never even reach the end of the day, and when i did the battery is almost on zero which is not very healthy for the battery.

For my use nexus 9 is not very good (at least at the momment). Maybe google improve the things in the future But for now ipad mini serve me better.

Edit:brightness around 25%.
[Nexus 9 General] Chyeo1979:
If I just surf and do nothing else, quite consistently draining about 10% every 30 mins, quite sad. Otherwise I really like this tablet.
[Nexus 9 General] con100:
I mainly use my tablet for browsing on Chrome, Reddit and Twitter. I always get 6 and a half hours of screen time.
[Nexus 9 General] darkchazz:
I think what the nexus 9 really needs is some sort of customizable performance profiles.

Example: underclock the CPU to 1.4~1.6ghz in the launcher and while using simple apps, and unlock full frequency when running a game (or benchmark, for those who like that sort of thing).

Meanwhile, I can easily get 8+ hours SOT browsing on chrome after blocking Ads, underclocking to 1.9ghz, and cpu governor tweaks, namely increasing frequency thresholds and decreasing the input-boost frequency to 1ghz from 1.5ghz

Heat has also been reduced to a minimum.
[Nexus 9 General] Chyeo1979:
Not expert on this. Any reason why Google would not do such tweaks given that it is proven it will increase the battery life tremendously?
[Nexus 9 General] R3Lax1:
I average 8 hours of sot over 2 days mostly on chrome.
[Nexus 9 General] Chyeo1979:
Stock lollipop?
[Nexus 9 General] R3Lax1:
Yeah, ads blocked, and flashed elementalx. Also decrypted, but that doesn't make a difference.
[Nexus 9 General] Chyeo1979:
Sorry, actually I meant is it stock lollipop out of the box without any rooting/flashing etc
[Nexus 9 General] JXulo:
I'm sorry for being skeptical but we are on page 49 and everytime someone has made claims like yours and we ask for printscreens they never appear, not even once! And when it happens is always with some modifications on kernel, cpu, rom etc etc.

On the other hand there are plenty of printscreens that confirmed what me and others experienced. Everyone who uses more than 20% of chrome is always with +\- 5 hours SOT.

I will believe when i see it, but we are on 49 page and nobody (completly stock) has show such a good values.
[Nexus 9 General] madsquabbles:
got to use my tablet from a full charge to 40% last night - had a 8:00PM dentist appt and when the meds wore off the pain kept me up all night:crying:

100% of the time was surfing in chrome (not beta) using USBhost's latest stable kernel, stock rom at 0% brighness - i got 4:11 min of straight use to 40% (i had to at least try and sleep), so about 15%/hour. so a possible 7hrs to 0% isn't bad, but sure as hell isn't great either. my note 8 that i'm replacing with this got 8-10 hours, smaller screen though.

how the hell did every freaking reviewer score 9+ on web browsing on stock? i'm pretty sure they had to be using chrome.

and, just like everyone else, chrome drained more battery than the screen. i've never seen results like that on any device and i've had quite a few. LP must be having some growing pains switching over to 64bit.

i ain't no apple guy, but you gotta admit they do have the stuff together and do make some pretty good hardware.

i just turned of network prediction in chrome and gonna see if that might help with the drain.
[Nexus 9 General] Metallice:
That's the purpose of a CPU governor. Interactive sets the frequency based on the current load.

Whether its set to favor performance or battery life is another question... Also whether it's configured well or not.
[Nexus 9 General] seanashmore:
So I'm now at 5h 40m SOT, compared to my ~6h30m last time. This time I played leos fortune and monument valley, each for roughly 45m. However I have noticed that on day 3 (today) the battery listing for monument valley has disappeared from my battery stats, there were no resets/crashes or the like in the entire 3 days so I'm not sure what is going on. Anybody else notice battery stats disappearing?

Also, does the CPU time in battery stats really mean CPU + GPU? Or is there a way to see GPU time, as in time it was highly active?
[Nexus 9 General] darkchazz:
I know, but seeing as the cpu is pushed to the maximum 2.3ghz every time an app or a new menu is opened, even with governor tweaks, I'd rather underclock and save some battery.

Heat dissipation is also quite terrible. HTC epic fail this time....

btw should we look forward to an m-kernel for N9 ?
[Nexus 9 General] madsquabbles:
Undervolting would be preferred if the CPU can handle it. Same performance with less power.
[Nexus 9 General] Metallice:
Yes it doesn't seem like the interactive is very smart from what I've been watching using perfmon. Too much high frequency use and staying there. Then again performance can be hit or miss. Odd.

M-kernel for N9? Maybe. I'm pretty busy now, but I cant say what the future will bring. I'd have to get a good one first. Might take a couple years at this rate.
[Nexus 9 General] cr0wnest:
I'm hoping to see M-Kernel for the N9 too. ;)

To those who rooted, by any chance is interactive the default governor for this device? It certainly feels like it. Interactive is a great battery saver when the device is sleeping, but the moment the screen comes on it always spikes on the high frequencies until you put it down.
[Nexus 9 General] madsquabbles:
another charge result from last night.

22% to 80% took 2h20m and ranged from 1000 to 1600 mA. 80% to 100% too 1h20m and stayed around 600-700mA.
[Nexus 9 General] RaymondScrott:
Long charge but is to be expected with 1.5 Amp charger and 6.5 battery. At Max charge it will be in excess of 4 hours and certainly more with battery charge modulation.. My concern is that even when tethered to a power supply, in use the available power continues to drop. Have not found it yet but where can I find the actual "live" figures in Amps of the charge rate and draw down.. The graph does not seem to tell you that.
[Nexus 9 General] madsquabbles:
I don't know how accurate gsam is, but its live reading shows anywhere from 1000 to 2100mA each time I check while browsing. If true then there's no way i cna think of to charge and use the tablet simultaneously. You can prolong the use, but it'll eventually drain.
[Nexus 9 General] RaymondScrott:
That is disappointing news. The least one should expect is for continuous use when on charge.
[Nexus 9 General] madsquabbles:
battery is great for ebook reading. ~30 min of reading and only dropped 2%. 0% brightness again, using moonreader, black bg with red text.
[Nexus 9 General] Chyeo1979:
Why are you using 0% brightness? :confused:
[Nexus 9 General] darkchazz:
I've been experimenting with gpu underclock using ElementalX kernel. Got some quite interesting results.

I've underclocked the gpu to get the raw performance down to Adreno 420, Mali T760 level, which is around 140-170 GFLOPS.

TK1 gpu perf is 326.4 GFLOPS with the stock 850mhz frequency. I've downclocked to 396mhz, decreasing the raw performance to 152 GFLOPS.

For comparison Apple A7 GPU yields 115 GFLOPS.

Now for the interesting stuff. Benchmarks will surely give lower scores so I decided to avoid that and try some games.

I've tried Dead Trigger 2, real racing 3, riptide gp 2, and beach buggy racing. Among others

As expected, heat and battery consumption have decreased tremendously while playing...

But to my surprise... There was no noticeable degradation in performance.. Every game ran as smoothly as it did before..

This could mean two things:

1) None of the games I've tried take advantage of all that horsepower. Perhaps no game in the play store does except for a few TK1 specific titles.

2) Nvidia's/Google's GPU governor is so inefficient it pushes the frequency to maximum even when the game does not need it.

Well, if you look back to nvidia's Tegra K1 announcement. They said that the TK1's Kepler GPU consumes 1.5 times less power than the iPad Air's GPU When configured to the same performance level.

I very much would like to take advantage of that :)
[Nexus 9 General] madsquabbles:
i always use all my tablets at 0% and occasionally go up to 15% - outdoors is obviously a different story. under normal lighting i keep my devices at 0. i've always wondered how most of you guys can use a tablet at over 25% brightness. that would blind me!:eek:

the majority of the time i have this tablet around -50% using lux (it just throws an overlay to tone down images, not acutally lowering the light output) because of how bright it is.

i probably could check myself, but do any of the kernels support undervolting? that would give decent boost too.
[Nexus 9 General] darkchazz:
None do.

ElementalX kernel did support voltage control but no longer.

See developer post here: http://xdaforums.com/showpost.php?p=56577225&postcount=22
[Nexus 9 General] R3Lax1:
Interactive is the default one, and most likely the main drain factor (appart from ads) is that by default hispeed_freq is 1530mhz, which isn't neccessary at all for denver cores.
[Nexus 9 General] cr0wnest:
That is interesting indeed.. Such a shame all that extra horsepower is used for unnecessary battery drain. :(

I havent rooted my tablet yet so I cant test it out myself. Perhaps custom kernels can do something about the GPU governor throttling the speed? More importantly, I wonder if NVIDIA/Google is aware of this but did not bother to fix it before release.
[Nexus 9 General] seanashmore:
When rooted, Is it possible to change the governor similar to cpufreq for Linux? Would moving to on-demand governor improve things for example? I think the N5 uses on-demand by default, I can't check right now thoiughg as I installed elementalX kernel and cpu-z lists the governor as 'elementalx'.
[Nexus 9 General] cr0wnest:
You should still be able to change the CPU governor and more by using kernel tweaking apps such as TricksterMod, this includes undervolting and overclocking if the kernel supports it. Unless of course, ElementalX is the only govenor available for the kernel, but i highly doubt it. Have not rooted and tried any custom ROM or kernel for the N9 so I cant give you my input here, but it should be the same across Android devices.
[Nexus 9 General] velocity90:
At 0 it's freaking bright already, I wish there was -10
[Nexus 9 General] madsquabbles:
i updated to USBhost's beta firmware and it does seem to help so far. i only did a 30 minute test, but it drained just over 1% per 10 min (74% down to 70%). a longer test is gonna be needed to see how much it helps, but so far it's doing good. cpu usage shows it barely went over 1ghz when browsing.

i did have the problem where it only charged up 10% in an hour, but a replug fixed it. i had the problem on stock also on my first charge.
[Nexus 9 General] USBhost:
There is
[Nexus 9 General] aleandre1974:
With Lux (available on the Play store), I manage to bring the brightness lower than normally allowed.
[Nexus 9 General] seanashmore:
For me the brightness is fine during the day but in darker scenarios I.e. in bed etc I use a handy free app called 'screen filter' which doesn't reduce the brightness has such but puts a dasrk filter over the screen so to speak -https://play.google.com/store/apps/details?id=com.haxor
[Nexus 9 General] madsquabbles:
using usbhost's kernel you physcially lower the brightness. downside is that you lose the ability to manually and auto increase/decrease the brightness until you run the script to unlock the backlight setting. so maybe making a tasker script or using some kind of helper app to make the terminal entry easy would assist in those times you set your bl too low for bright conditions and can't see anything. a reboot might accomplish the same thing i think.
[Nexus 9 General] velocity90:
Yes, I use that too. Brilliant and simple app