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Hi there!!
Seems to me no one hasn't began this knd of theme. So. Off. info:
Qualcomm MSM7201a
Two cores
ARM11 + ARM9
528 Mhz (one stated speed for two cores...)
So what is G1's heart for real?
This is quotes from here
#1
Jean-Baptiste Queru 26 нояб 2008, 20:37
Indeed, the CPU in the G1 is clocked lower than its maximum rated
speed to conserve battery life. It's running somewhere between 300 and
400MHz if I remember correctly.
JBQ
Click to expand...
Click to collapse
#2
jdc4429 27 нояб 2008, 17:04
Hi Jean,
So your saying that the CPU speed is not controlled by the Android
software?
I was looking through the code and found this in the arch/arm/mach-msm/
clock.c file...
617 #define CPUFREQ_TABLE_MAX 4
618 static struct cpufreq_frequency_table cpufreq_table[] = {
619 { 0, 81920 },
620 { 1, 122880 },
621 { 2, 245760 },
622 { 3, 384000 },
623 { CPUFREQ_TABLE_MAX, CPUFREQ_TABLE_END },
624 };
It looks like the max speed is set to 384mhz and it seems it can be
easily changed.
It also seems that the phone already downshifts the CPU based on this
table and the
screen_open/closed speed setting...
702 if (screen_on) {
703 policy->user_policy.min = cpufreq_table
[2].frequency; // 245mhz
704 policy->user_policy.max = cpufreq_table
[3].frequency; // 384mhz
705 } else {
706 policy->user_policy.min = cpufreq_table
[0].frequency; // 82mhz
707 policy->user_policy.max = cpufreq_table
[2].frequency; // 245mhz
708 }
Sure looks controllable to me through Android. Is it really that hard
to add a setting to allow min/max settings
to be adjusted by the user?
Thanks
Jeff
Click to expand...
Click to collapse
#3
Romain Guy 26 нояб 2008, 20:39
> Can that
> be changed in software on the fly and was it set below maximum speed
> to help with the battery issue?
No and yes
> Also is anyone working on adding hardware acceleration so we can take
> full advantage of the processor?
We have a prototype of SGL running on top of OpenGL (it was actually
shown publicly in the SDK 0.9) but it's not the correct solution at
the moment.
Click to expand...
Click to collapse
Coclusion:
1) Google DevTeam does not know, or don' wanna tell, ca we\how to change CPU's speed or\when it would be possible to get the hardware accelariotion etc.
2) From stated 528Mhz we get 384Mhz maximum, as stated by Jean-Baptiste Queru and the code quote.
Both these I suppose seems not fare for us users)
So, can it be solved through the OS modifing??
Oh yeah that's another good point -- almost all of my experience on mobile
hardware has been that the memory bus speed was far more of a performance
bottleneck than the CPU was. It generally just wasn't useful to run the CPU
at its fastest speed and consume more power, because most of what it would
be doing was sitting there waiting on memory.
Click to expand...
Click to collapse
I don't know what is more important, the memory/cpu ratio working at its best or battery life. We'll have energy plans soon for android me thinks..
interesting... Anyone want to give it a try?
It's very worthwhile to read the entire thread:
http://tinyurl.com/9kme8v
Of particular note, the effect on battery life of clocking the CPU at full speed, and the apparently minimal performance boost.
Of real interest, and the very obvious bang for the buck, is the speed of Dalvik. Note that it's 7-8x slower than comparable JITs. About in line with what you'd expect, but it does imply that if we want to see some serious speed increases - and, I would think, battery life improvements - replacing Dalvik would be the obvious place to start. Or making it JIT, of course.
might be but lets say im at home plugged in or what not... then we could scale our CPU... like BatteryStatus or integrate it into an app somewhat like Locale or Power Manager...
End users look at the End result. my phone is rated at 528mhz and it is running slightly over half its rated operating speed. Battery life? Give me 528mhz and let HTC and Tmobile Recall there $h*tty batterys
The only advantage I can think of for this is for demanding games for instance but any other time its good to have it under clocked to save on battery juice. and the phone is fast enough running at half its rated speed!
Phil
philje123 said:
The only advantage I can think of for this is for demanding games for instance but any other time its good to have it under clocked to save on battery juice. and the phone is fast enough running at half its rated speed!
Phil
Click to expand...
Click to collapse
once you get demanding apps installed such as hello aim. phoneplus dgalerts etc there is constant hiccups and the phone becomes bogged down like i said give me 528mhz and let htc,tmo replace there $h**ty batteries didnt they hear over a year ago there was a huge advancement in nano tech for batteries
diabolical28 said:
once you get demanding apps installed such as hello aim. phoneplus dgalerts etc there is constant hiccups and the phone becomes bogged down like i said give me 528mhz and let htc,tmo replace there $h**ty batteries didnt they hear over a year ago there was a huge advancement in nano tech for batteries
Click to expand...
Click to collapse
True, but *if* it is the CPU which is bogging down (which I am not convinced is the case), the solution is as I stated - speed up Dalvik - not to put the CPU into a mode which drains the battery down even more quickly than it does today. If the fix is to clock the CPU at a higher rate (which again, seems not to be the case), that's only a stepping stone to the ultimate solution, which is going to be removing some apps, since the battery life is marginal right now anyway.
The reason why Android is underclocked is posted in the full thread. After a certain point, the increase in speed you get by bumping up the CPU slows down, because it's limited by FSB speed. An example of this (not real numbers), is that a CPU running at 50% speed could actually be closer to 75% speed.
Sure, the CPU CAN run at 100% speed, but after the FSB slows it down, it'll only be 75%. So after a point, increasing CPU speed isn't worth it.
hmm
i wonder if we would get an app too monitor it or
under and overclock by adjusting a slider
anywhere from 50% to 150% or whatever is possible
that is anywhere from 264Mhz to 798Mhz which would be amazingly fast
gary, might as well just save your breath.
I believe JF has already tested some code to do this, but mentioned that it is highly unstable.
dirr said:
I believe JF has already tested some code to do this, but mentioned that it is highly unstable.
Click to expand...
Click to collapse
Adjusting the speed breaks things, at least so far anyways. But like he said JF is playing with it.
djind said:
I don't know what is more important, the memory/cpu ratio working at its best or battery life. We'll have energy plans soon for android me thinks..
Click to expand...
Click to collapse
Sure, it might not be entirely "worth" it in terms of performance/battery ratio... but that doesn't mean it isn't worth a try. People keep saying "don't bother" but nobody has actually tried an overclocked G1. Maybe it's worth it for demanding gaming or apps while the phone is (gasp) plugged in.
back when i had my wing and so did ttran. Which uses the OMAP processor it was able to overclock over 100mhz faster than it was meant to go. Had real good luck overclocked to 288mhz. Which made the phone run at the speed that it SHOULD have ran at... including faster loading web pages, faster loading everything basically. Which hardly is an issue with the g1, but imagine how much more snappy it would be with an extra 100mhz also? People say its not worth it and it drains the battery more.... umm... if anyone here owns a g1 (surely hope so at least!) you probably know that the battery sucks anyways and needs charging all the time. Would love to see a good OC app made for the g1 =-) (with scaling like battery status was for the wing, which underclocked when screen was off, overclocked when screen was awakened which was amazing for battery life, as the phone doesnt need much power to accept a call, but when the screen is lit.... scaling occurs and it bumps it right up to 288mhz)
I think its well worth a go.
We could start with very small increments.
Gary13579 said:
The reason why Android is underclocked is posted in the full thread. After a certain point, the increase in speed you get by bumping up the CPU slows down, because it's limited by FSB speed. An example of this (not real numbers), is that a CPU running at 50% speed could actually be closer to 75% speed.
Sure, the CPU CAN run at 100% speed, but after the FSB slows it down, it'll only be 75%. So after a point, increasing CPU speed isn't worth it.
Click to expand...
Click to collapse
I think the question is... Are there any circumstances where this may help...
And either way how difficult is it to add a control under settings to allow you to modify the default method?
You could basically apply the same argument to anything... Until someone tries, we will not know for sure. What next? Don't bother trying to add a swap file cause it may not help? Don't bother trying to speed up Dalvik cause it will take too much memory?
That's the fun of open source...
jdc4429
FSB could really be the bottleneck here. From my experience overclocking mobile CPUs (PXA255, PXA263, PXA270, Samsung 300Mhz, TI OMAP 850) several percentage change on FSB speed or Memory speed could make significant performance changes.
The last WinMob device I had - Dell Axim x51v had a PXA270 [email protected] Pumping the bus from 208Mhz to 230Mhz and the CPU speed from 624 to about 700 did abput 50% improvement in several bencmarks (floating point, integer calculations, memory speed, graphics subsystem).
On the other hand pumping the CPU to 1014Mhz, (0.99GHz, the highest 24/7 stable for my device) while lowering the FSB to 185Mhz (23Mhz drop) led to about 10% lower result than at stock frequencies.
700Mhz CPU, 230Mhz FSB was totally 24/7 under stress tests with almost no extra heat, providing aboyt 50% extra performance, while battery life was about 30-40% shorter.
My experience with it showed that it could be worth for short speed bursts, while running many apps. When you are finished you return to normal frequencies.
Wow! Thanks for the info man!!
Thus we can see, that by increasing the CPU up to it's stock 528 Mhz would be perfect?
it will be perfect when the speed of the cpu uses 528Mhz and auto adjusts: high speed - mid speed - low speed - sleep, "ondemand"
android should use ondemand kernel module which does exactly that. (maybe this cpu cant do that?)
I have a few questions about OC/UV kernels or rather the theory behind them, particularly the UV part.
My natural instinct is to believe that when the voltage is dropped that the amps would increase so the CPU would still have the same amount of power to run the CPU at a particular frequency. This of course would negate any advantage in UV. I assume that my assumption is wrong or someone that really knows something would have pointed it out.
On the practical side of things, if the above is not true does the phone/cpu use the same amount of power if it is running at 216 Mhz with 770 mV as it does running at 400 Mhz with 770 mV. Same question would also apply to high frequencies that are UV and their relationship to heat generation.
Not sure about smartphones, but with my computer, I can drop 10 watts just from under volting when idle. Under clocking makes an even bigger difference. I'll get some exact numbers in a few mins, this got me wondering lol.
Edit:
At the wall my PC will pull 111 watts @ 1.6GHz idle. @ 4.5GHz it pulls 137 watts on idle.
I wish I had a link I could provide, but the basic science is this (learned this from Calkulin, Ziggy, and trial and error with my evo):
uV:
When you uV your cpu, each frequency step draws less power. For example, a non-uV'd cpu might draw 1300 mV at 1000 MHz whereas a uV'd cpu might draw 1225 or 1250 mV at 1000 MHz. There is no sacrifice in performance. You also get a cpu that runs cooler because it is drawing less power. The combination of these things means better batter life because you are drawing less power (obvious) and generating less heat (heat is one of the enemies of Li-ion batteries holding a charge).
But not all chips are the same, and some tolerate lower voltages better than others. If a particular voltage is too low, you get crashes, reboots, and other things like that because voltages that are too low make things unstable.
OC:
The theory behind OC is that the higher frequencies allow you to complete tasks faster. If the cpu can complete a certain task in a shorter period of time, it will be in use for less time overall, thereby allowing it to return to its idle frequency faster and stay in its idle frequency state longer. Again, this combination increases battery life because the power drawn from the battery is less. You can think of this as a "race to the finish" situation.
For example, if you OC to 1100 MHz, you might complete a task in 1.5s, whereas at 1000 MHz that same task might take 2s. The cpu actually works for a shorter time and returns to idle 0.5s faster. Add this up over an entire day, and your cpu actually spends more time at idle when OC'd than when not OC'd.
Again, just as with the uV, not all chips can tolerate maximum OC and just become unstable. That's why you've seen some G2x chips be able to run at 1500 MHz and be stable, while others can only tolerate 1300 MHz. Instability by trying to OC the cpu too much will lead to the same types of problems as lowering the voltages too far.
OC & uV together:
When you OC and uV, you allow the cpu to run at a higher frequency and draw less power at the higher frequency. This means you get tasks done faster and use less power to complete them, which allows the cpu to return to its idle frequency faster.
This is a real-world hypothetical: Imagine you have a cpu running at 1100 MHZ at 1300 mV and 1000 MHz at 1300 mV. When this is the case, your OC'd/uV'd cpu completes a task faster (in 1.5s rather than 2s) and actually ends up drawing less power than the non-OC'd/non-uV'd cpu because it completes the task faster and returns to idle sooner. When you add this up over an entire charge cycle, you should get better battery life.
This is a message from a developer who is in a team who develops a kernel with a very large overclock. Do not take this is an idiot babbling, read this and take it to heart as this is very important.
I want to talk to you about overclocking our phone and how dangerous it can actually be. I love overclocking, and have overclocked my main computer, and I overclock my phone, but my overclock (as you can see from my signature) is very mild. A simple 800MHz overclock.
When we first got overclocking on our phone (thanks to Fugumod), we were around 800MHzish and it gave a nice boost. It got up to 1GHz and it gave another good boost. Over time, we have discovered the phone works at high speeds, now 1366 in Fugumod, and 1400 in G3MOD. Now if you look at these speeds and compare it to the original clock speed on our phone (667MHz, or you can look at the Spica which has the same CPU but with a larger transistor process: 800MHz), this is a 204% overclock on Fugumod and 209% on G3MOD.
Now let's put these percentages into perspective: on your desktop computer, a 200% overclock is normally only possible with serious cooling: water or liquid nitrogen, and we are attempting to do this in a PHONE with NO cooling, and NO ventilation. Furrthermore, it is kept in our pockets beside our thigh muscle: the largest muscle in our body and it emits a large amount of heat. These are not ideal conditions for a CPU to be kept in, especially when it is in a fragile state such as overclocking. We are lucky however because phones have clock governors which clock it back when it is idling to conserve power.
When you overclock the CPU, you must also overvolt it to keep the system stable while overclocked. However the downside is that if you overvolt your CPU, you will use more power, and also reduce the lifespan of our CPU. Let me show you how much more power is required to run the phone at 1.4GHz.
Now, as we don't know the exact power consumption of our CPU, I will assume the power consumption is 100mW. In overclocking a desktop computer, we use this algorithm:
Code:
OC Wattage = TDP * ( OC MHz / Stock MHz) * ( OC Vcore / Stock Vcore )^2
So that means 100 * (1400 / 667) * (1525 / 1200) ^ 2 = 338mW. That is over 3 times the power consumption of the CPU at stock speeds. That also in turn effects the lifespan of the CPU as the transistors are both having to work twice as hard (as the CPU clock is twice as high) and are drawing three times the power consumption, this means the CPU will last 6 times less at 1400MHz.
When we were starting out with overclocking our phones, we didn't have a lot of the nice new features we have discovered that boost performance but now that we do, these huge overclocks just aren't as necessary anymore.
TL;DR
Guys, our phone can go at 1.4GHz or 1.36GHz, yes. But is it a good idea to keep it at those sorts of speeds? No. The reason marcellusbe and the G3MOD team provide such HUGE overclocks are for rare occasions. When the phone is just doing nothing, we expect you to put it back to 667/800MHz, but when you are wanting to play Angry Birds or emulate Castlevania 4 or something, you put it up to 1400MHz, but put it back again once you are done. 24/7 usage at 1400MHz or 1366MHz is DESTROYING your CPU and your battery.
USE OVERCLOCKING WITH EXTREME CAUTION
Extra Information
Here is a graph to show the power consumption increase from running the CPU at higher overclocks and also the reduction from undervolting.
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Even an i7 is rarely oced to 200% - its too much and can be dangerous
cdesai said:
Even an i7 is rarely oced to 200% - its too much and can be dangerous
Click to expand...
Click to collapse
Precisely my point.
Nice one mate...
Maybe when you get time just include UnderVolt also...People are waiting for some stuff to come up for that also...
dharamg3 said:
Nice one mate...
Maybe when you get time just include UnderVolt also...People are waiting for some stuff to come up for that also...
Click to expand...
Click to collapse
+1 For that too
Nice information. I always used to keep my phone to 1200 mhz. Damn should reduce it now
Thanks, excellent info.
Sent from my GT-I9000 using Tapatalk
I never try to go beyond 800Mhz
I think it is sufficient for daily use
(More than sufficient)
exactly.... i was going to post somthing like this
when u need that boost (like for ps1 emulator or hd games) us upto 1.3ghz
but otherwise just leave it at 800-900mhz...
u dont need crazy oc all the time!
Doesn't SetCPU (or any other app for that purpouse) do exactly that? If you set scaling and min/max freq. accordingly? What is the difference beetween that and setting in manually?
Gud info mate......
Governer should be Ondemand right ????
Hm, a guy called Kyrillos told me, that normal voltage at 667MHz is 1200mV. So, in newest g3mod, from 500MHz on, its higher, at 800MHz its already 0,1 volt above max in stock.
So how dangerous is it to let it allday at [email protected] ?
DaBigFreak said:
a guy called Kyrillos told me,
Click to expand...
Click to collapse
He s a recognized developer. A very good one infact. He was right by the way. Its only the faulty reading.
---------- Post added at 01:32 PM ---------- Previous post was at 12:54 PM ----------
Hillbeast excellent, excellent info. That s the precise reason I don t use high overclocked kernels. Maximum I goto is 800MHz.
raja4sure said:
Gud info mate......
Governer should be Ondemand right ????
Click to expand...
Click to collapse
Yes. I use it mostly. Other devs and experienced users here as well for what i've noticed. Or conservative which saves battery because it scales freq more gradually. http://www.setcpu.com/ - http://www.setcpu.com/#7
And profiles, especially the Temp and screen off. Prevents from overheating and exscessive battery discharge, respecitvelly.
DaBigFreak said:
So how dangerous is it to let it allday at [email protected] ?
Click to expand...
Click to collapse
Probably very. But overclocking in general shortens life span of electronic components, primarily because of increased heating. If that worries someone that it is probably best not to overclock at all.
I personally see no difference between manipulating cpu freq manually or by using some app to do it when necessary. If I'm wrong then please feel free to elaborate.
dharamg3 said:
Nice one mate...
Maybe when you get time just include UnderVolt also...People are waiting for some stuff to come up for that also...
Click to expand...
Click to collapse
I will update this thread and I hope it will actually get stickied as it's quite important information in my opinion and it could save some peoples phones.
mrvek said:
Doesn't SetCPU (or any other app for that purpouse) do exactly that? If you set scaling and min/max freq. accordingly? What is the difference beetween that and setting in manually?
Click to expand...
Click to collapse
SetCPU will obviously set the max and min settings, but in an ideal situation you will want to have a mild overclock (or none at all) if you are just using for phone for normal functions such as TXTing or browsing or something like that, but SetCPU can't detect when you are wanting a more intense operation such as a game, so you're best to adjust it when you are needing it and switch it back.
I keep a SetCPU widget on my home screen to do that.
DaBigFreak said:
Hm, a guy called Kyrillos told me, that normal voltage at 667MHz is 1200mV. So, in newest g3mod, from 500MHz on, its higher, at 800MHz its already 0,1 volt above max in stock.
So how dangerous is it to let it allday at [email protected] ?
Click to expand...
Click to collapse
The stock voltages for our phone at 667 is 1200mV, yes. At 1300mV you will notice a mild increase in consumption.
If we follow the same algorithm in the OP:
Code:
OC Wattage = TDP * ( OC MHz / Stock MHz) * ( OC Vcore / Stock Vcore )^2
We get (again, assuming the standard consumption is 100mA) 100 * (800 / 667) * (1300 / 1200) = 140mA. Yes, it's higher but not too much higher. If you UV it by 50mV @ 800MHz you'll go to 130 and at 1200mV it'll be 118mA.
Overclocks like this are still not 100% safe, but they are nowhere near as dangerous as a 300% power consumption increase.
This is the Information I was looking for past 2-3 weeks. Finally you posted it here.
Thanks hillbeast
Hey man. I really appreciate your effort to inform. I just would like to add something.
Overclock: in modern cpus power consumption increases almost linearly with clock. Let us say linearly to be safe. It means double clock double power (and so heat)
Voltage: when you increase the voltage the power increases approx quadratically (double voltage for times power). But also higher voltage means stronger signals in transistors and so higher stability.
Heating and lifetime: the heat decreases the lifetime of electronic components but not in a linear way. Please also note if a circuit does not die very soon (infantile mortality) it will last very long in normal conditions. So even if it was cut by half starting from the normal 10 years expected lifetime it would be anyway long for a phone.
So it is clear voltage is much more important than clock for power consumption. Decreasing the voltage you could have an overclocked cpu which consumes and hests up less than the stock one. Of course it is less likely to be stable.
Personal computer cpus needs cooling and are difficult to overclock because they become very unstable when overclocked so you have to increase voltage.
Finally to be clear I want to repeat your lesson.
DO NOT OVERCLOCK UNLESS YOU REALLY KNOW WHAT YOU ARE DOING. and don't complain with developers if your phone will break.
Sent from my GT-I5800 using XDA App
After reading this, I will never overclock more than 1GHz. Thanks
I agree extreme 200% overclocking is harmful to cpu and disagree with some of the points.
I don't think wattage and tdp formula are correct. If it is correct in reality battery should drain in 1/3rd of the stock time and should heat up immediately. we are just increasing the power supply in mv which is 1200 to 1500%. That means 25% power increase.
When the phone is in idle (no music, wifi, data ...) mode cpu/armcore is completely turned off. That means no frequency, no power supply and no heat. Other peripherals have separate clocks and they will keep running in idle mode. This is the difference between desktop and phone cpu.
frequency is 'no of times turning on and off transistors in a circuit per second'. In fact cpu's are designed to work at much more frequencies than stock. But stock frequency is decided by considering various operating conditions worldwide and $$. Personally i use 1020Mhz and phone operates like stock frequency.
I don't agree with one of the last statements:
hillbeast said:
So that means 100 * (1400 / 667) * (1525 / 1200) ^ 2 = 338mW. That is over 3 times the power consumption of the CPU at stock speeds. That also in turn effects the lifespan of the CPU as the transistors are both having to work twice as hard (as the CPU clock is twice as high) and are drawing three times the power consumption, this means the CPU will last 6 times less at 1400MHz.
Click to expand...
Click to collapse
Assuming you use setcpu, your phone spend most of the time in standby. if you use your phone a lot, it will be in standby 70% of the time.
Assuming that when your phone is not in standby the clock is automaticly set to 1400 (which is probably not, but we're doing worst case), your phone will be overclocked 30% of the time.
If your statement about battery drain is correct, the processor will use 160% more battery than usual. This, will not result in a huge battery drain, because actually, the processor is draining very little battery compared with things like display, wifi, 3g and so on.
If your statement about lifespan of the cpu is correct, the lifespan of the cpu is reduced to 75%. Considering that a cpu can last years and that you usually throw your phone away way before the cpu stops working, doesn't seem like a big deal to me.
That is true. Unless you run your phone 24/7 at max OC speed and phone heats up excessively there really should not be problems. That's why we have good apps and scaling governors that save the cpu and battery. In my case the phone spends most time at 400Mhz, then on 800, then 1400 then other freqs (based from setcpu report - info → time in state). Main profile beeing 400/1400, ondemand. And temp doesn't go over 31°C on daily use. What increases temp are mostly games but for that i use several setcpu profiles (in this point i disagree with hillbeast and the ability of setcpu to know my specific requirements. I know that it can't know what i need and when but if I set manually the requiered freq (max) to play a game the phone would heat up significatly (angry birds for about 30 mins gets me to 36°C - relatively high). And then i need profiles not to overheat the phone. And now when I already have profiles, why not let everything be automatic?).
Please don't get me wrong, I agree that OC-ing is quite risky and it should (must‼) be done with great caution and that is an implicit requirement.
Does anyone else think the CPU running at 480Mhz-800Mhz screen on is a bit too high? It's more than capable running at a 122Mhz minimum - heck, even 19Mhz, although it doesn't spend much time at 19Mhz. Also, if perflock is enabled, it locks itself to 245Mhz only when screen off - still seems a bit too high for me, considering there's lower selectable frequencies.
Anyone who's temprooted their device: Are you using SetCPU to change the CPU frequencies/disabling perflock? I have my Chacha running at 800Mhz max / 122Mhz min perfectly fine (running my battery down for a while to see if the battery life benefits) - although occasionally, it still locks itself to 122Mhz even after turning the screen on for about a minute, which I believe is a kernel issue
For reference, the frequency options are: 19Mhz, 122Mhz, 128Mhz, 245Mhz, 480Mhz and 800Mhz.
128Mhz doesn't actually work, and if it's selected, it uses 245Mhz instead even though SetCPU says "128 min"
Unfortunately I can't help you, but I'm totally interested on the subject!
As far as I know and tested on other android devices, setting the CPU freq too low will cause some unwanted behavior like being unable to power up the screen. Happened on a Galaxy S, where I've set the freq to 19Mhz (or something similar) and I've locked the screen. Pressing the power button did nothing so I had to re-flash the rom.
really need low cpu frequency?
low frequency is certainly not good. For chachar, I just hope 600 frequency could be done the hardware itself(not by setcpu). I hate the power consumption is too big, and the machine is easy to get hot.
Alex C. said:
As far as I know and tested on other android devices, setting the CPU freq too low will cause some unwanted behavior like being unable to power up the screen. Happened on a Galaxy S, where I've set the freq to 19Mhz (or something similar) and I've locked the screen. Pressing the power button did nothing so I had to re-flash the rom.
Click to expand...
Click to collapse
True, setting the frequency too low is bad for some devices, but in my personal experience with my Chacha, I can actually run mine at 19Mhz min/800Mhz max and have little to no problems, since it doesn't spend much time at 19Mhz anyways. (I use no SetCPU profiles, as I feel they have little to no benefit on battery life.)
All of this is just a thought though, since HTC set the minimum to 480Mhz with the screen on which seems way too high to me :/
Also, locking the CPU to a single low frequency was actually a bad thing on one of my old devices, a Desire Z, which usually caused wake problems, etc.
semanty said:
low frequency is certainly not good. For chachar, I just hope 600 frequency could be done the hardware itself(not by setcpu). I hate the power consumption is too big, and the machine is easy to get hot.
Click to expand...
Click to collapse
600Mhz is possible indeed - the MSM7227 processor that the Chacha uses is actually rated at 600Mhz, but HTC factory overclocked it to 800Mhz. It would require a custom kernel to have 600Mhz added back in
anyone thought of a way to undervolt???? i mean use less voltage for each frequency..am trying to search for kernels to flash but cudnt find any
Coming from the HTC Desire, where SetCPU was the only to manage the CPU, I have developed a habit of using SetCPU with several frequency profiles and different governors for various situations. For instance, I use battery<80, <60, <40, <30, screen off, temp >40, >50, and a charging profile. For governors I use lulzactive2 for higher frequency ranges, interactive for mid range frequencies and on demand for the lower frequencies. Oh, this is all with the latest matr1x kernel.
Seeing how a lot of ROMs allow extensive controll of the CPU I was wondering if it wouldn't be more efficient to just set a min/max frequency, chose a governor, turn deep idle on (which is off while I'm using SetCPU) and leave it be.
What are your thoughts and experiences on the matter?
/// endmessage / COMPUTOR5000
profile ? that's completely unnecessary...
just set governor and min-max is enough.
we have NSTOOL, so looks like extended ROM controll also not necessary because not good enough compare to NSTOOL , but lots lots ROM has it build-in
I've never bothered with profiles. I can feel if the phone needs a break from the heat and performance is good for me with 100/1200 set and slight undervolting.
Battery life while idling won't change, only while using intensive apps, and with deep idle working and max freq screen off, music playback and the likes drains very little battery.
Try it and see, you need to be comfortable with it.
I agree with qtwrk. Profiles are, in most cases, detrimental. The following is especially true since Deep Idle was implemented: always let the CPU run as fast as possible to save energy. Sounds counterintuitive, but here's why: while lower CPU frequencies in general consume less energy PER TIME than higher CPU frequencies, the faster the CPU can finish it's job, the faster it can return to energy saving states. So in the end, reducing CPU frequency actually uses more energy... Just overclock to save values, use undervoltage to set lowest possible voltage values and go to sleep.
What's the minimum you can set the screen off max frequency so that music playback isn't choppy?
Also, is the phone always idle on screen off, or does music playback, or any other activity make the phone come out of idle, even if the screen is still off?
/// endmessage / COMPUTOR5000
zyrill said:
I agree with qtwrk. Profiles are, in most cases, detrimental. The following is especially true since Deep Idle was implemented: always let the CPU run as fast as possible to save energy. Sounds counterintuitive, but here's why: while lower CPU frequencies in general consume less energy PER TIME than higher CPU frequencies, the faster the CPU can finish it's job, the faster it can return to energy saving states. So in the end, reducing CPU frequency actually uses more energy... Just overclock to save values, use undervoltage to set lowest possible voltage values and go to sleep.
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Very good point, for exemple cpu at 1000 MHz takes 1100 juices per second and 10 seconds to finish a task, total cost 10 x 1100 (11000 ) juice
If it runs at 1200 MHz takes 1200 juices per second, same task only needs 8.34 seconds, 8.34 x 1200 (10008) juices... this isn't real just number assumption and theoretically appears that way
Sent from my Nexus S using xda premium
I agree with everything that was said here and actually posted about this very topic earlier on in the matr1x thread in regards to the lulzactive settings. People putting settings too much towards battery saving are actually not getting battery savings. They are making the CPU run longer and therefore more cycles and more power. Profiles are a bad idea too. They cause problems.
I decided to ask hear instead of creating new thread, etc.
In the amazing post of droidphile http://forum.xda-developers.com/showthread.php?t=1369817 there's an information about SGS II, that
'energetically efficient' frequency for CPU is 200 mhz
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(it's Cortex-A9).
And what about Cortex-A8 on Nexus S?
droidphile also says that on Milestone (Cortex-A8) 550Mhz is the frequency used in the calculations based on the optimal energy to run. Don't know what's the source of this info...