When I worked on some ARM embedded projects, we used the zero wait state SRAM of the ARM chip to speed up our applications. The performance benefit is tremendous. There is no published way to access it on Windows Mobile, but there probably is a way. Anyone have a clue? Most likely it will be addresses lower or higher than the video buffer.
Thanks,
L.B.
logical quest..
hi.!
I was interested for your topic..
i know that there are some app
that permise you the overclocking
of texas omap...what is this? another
type of overclocking? i think that is
very dangerous way..the risk for the cpu
fusion is high..!so..i don't think that is
a good idea..and the margin that you have
for example with an 200 Mhz processor is minimum for
a good overclocking..if i were you, i should not force the default limit setting by the HTC company.. Ppc device haven't a fan for heat's dissipation (it isn't a PC!) , so when you use the PDA and consequently you make his overclocked cpu under pressure, its go aut of order and..Bang.! do you agree?
What I'm asking has nothing to do with overclocking. The DRAM in PDA's is slow compared to how fast instructions can execute. Built into most ARM CPUs is a small amount of static RAM (usually 256K or 384K) that is usually used for the video buffer. The excess memory is useful for storing data for your applications to run quicker since it won't have to wait for the RAM.
I personally do not overclock my PDAs.
is this a sort of SecondLevelDataCache as Winzozz XP?
devilpera64: This is SRAM as in STATIC RAM. It's a little area of high speed memory (0 wait state) built onto the processor silicon. It's quite useful for use as a video buffer and for speeding up critical sections of code.
This guide is meant for ALL smartphones that runs the Interactive governor, copy-pasted here for better visibility. Credits goes to @soniCron for starting up the guide and @Alcolawl for further implementing it.
The Introduction
So, I tried copy-pasting the entire thread and realised it looks ugly therefore I'll rewrite it to be more simpler and straightforward.
Imagine a car with manual gears, you choose what speed is best suitable for the road conditions. Going into a curve? Best slow down. Clear straight road? Go fast so you reach the destination safely and efficiently.
That's what this guide aims to do with the Interactive governor, based on the CPU load it will choose the best and the lowest frequency to complete the task without compromising performance.
For example, if you scroll your Facebook page your CPU might clock up to the highest frequency for smooth scrolling. Now lower the frequency one step down and you may find that it's still smooth, so why isn't it choosing that instead? Don't blame the phone companies or Google, that's just a way of ensuring performance at all times. This guide will push the limits of that capability.
By default, the Interactive governor will jump from lowest speed to a "nominal" speed under load, and then scale up from that speed as load is sustained. That is lovely, but still too twitchy to provide serious efficiency and power savings. It spends most of its time at 2 or 3 clock speeds and barely hits other clock speeds that are ideal for other tasks or usage patterns.
Instead, what we want to do is configure it to handle different types of loads in different ways. A load suited for scrolling through a webpage is not the same as a load suited for downloading/processing streaming video is not the same as a load suited for snappy loading of an app is not the same as a load suited for high performance gaming. Every kind of load has different tolerances at which their minimal speed is indistinguishable from their maximal speed.
To understand what's best under a variety of tasks, we have to identify two types of load profiles: nominal clock rates and efficient clock rates.
Click to expand...
Click to collapse
Nominal Clock Rates
Nominal clock rates are the minimum CPU clock rates that perform a given task smoothly and without stuttering or lag. To find the nominal clock rate for a given task, turn on only the first CPU using the Performance governor and turn them both down incrementally until you find the minimum clock rate that works best for what you're trying to do, without introducing lags or stutters. (If you have a CPU or kernel that hotplugs individual cores, multiply that clock speed by your number of cores.) Keep the 2nd CPU on the Powersave governor with the lowest frequency your kernel supports. (Or turn it off completely if hotplugging allows.)
Remember what was said about scrolling FB pages? This is it.
Efficient Clock Rates
Efficient clock rates are CPU clock rates that are unique in that they are the most optimal frequency given the range of voltage requirements. If you map out the frequency jump and the voltage requirement jump between each of the available clock rates, you will find that occasionally the voltage requirement will jump significantly without the frequency jumping proportionally to the previous differentials.
For example, using stock voltages, the EvoLTE's msm8960 chipset clock/voltage ratios jump significantly higher from 702Mhz to 810Mhz than the ratios from 594Mhz to 702Mhz.
Imagine a staircase with steps of different heights. You climb these stairs better depending on the height of each steps, do you skip some steps if you can reach the next one easily? Or do you take one step at a time because they are too high?
Clock Rate Biases
Using the information provided above, figure out both your nominal clock rates for the tasks you perform most often and your efficient clock rates depending on your kernel/custom voltage settings. For me, since I cannot determine the efficient clock rates, I use the nominal clock rates listed above. For the tasks I generally perform on my phone, my nominal clock rates are as follows:
Idle - 384Mhz
Page Scrolling - 600Mhz (Tested by browsing FB on Chrome browser cause they're intensive enough)
Video - 787Mhz (Same thing, watch 60fps videos on different resolutions on the Youtube app to detect stutters and lags)
App Loading - 960Mhz
High Load Processing - 1440Mhz
(Note that you must calculate the values that are optimal for your phone for best battery and performance! Each phone is different because of the ROM, kernel, background tasks, etc!)
With this done, you will want to start the fine tuning phase! Correlate the efficient clock rates with their closest nominal clock rates, similar to below:
(This section of the guide is INCOMPLETE because I do not know the clock rate voltages for the Nexus 5X. If you know these, please post in the comments and I will update the guide!)
Idle - ???Mhz efficient / 384Mhz nominal
Page Scrolling - ???Mhz efficient / 600Mhz nominal
Video - ???Mhz efficient / 787Mhz nominal
App Loading - ???Mhz efficient / 960Mhz nominal
High Load - ???Mhz efficient / 1440Mhz nominal
Now that we know what are the most efficient nominal clock rates we want to focus on and what the most optimal are for what we want to do, we will start low and scale up as necessary. It's always better to begin with underperforming and tweak the settings upward until we're satisfied with the performance of our target tasks.
In its default state, the Interactive governor has a hair trigger that will raise and lower the clock rates, which means it spends too much time at unnecessary clock speeds, wasting power, and scales down too quickly, leading to stuttering performance. We will take advantage of a seldom used feature of the Interactive governor. Specifically, that with which it determines when it is okay to scale up to each higher clock rate, on a frequency by frequency basis.
We have two primary goals: respond as quickly as possible to each load request for a lag free experience and exceed the desired clock rate for a given task as little as possible. To do this, we will instruct the Interactive governor to trigger certain clock rates in different ways depending on our expected load.
I won't explain all of the settings of the Interactive governor--there are plenty of summaries all around. (Go search now if you don't know what any of the settings for Interactive governor do. I'll wait here.) However, I will explain an incredibly powerful feature of the Interactive governor that is rarely included in those summaries: multiple frequency adjustments.
The above_highspeed_delay setting, for example, defines how long the governor should wait before escalating the clock rate beyond what's set in highspeed_freq. However, you can define multiple different delays that the governor should use for any specified frequency.
For example, we want the above_highspeed_delay as low as possible to get the CPU out of the idle state as quickly as possible when a significant load is applied. However, we don't want it to jump immediately to the fastest clock rate once it's gotten out of idle, as that may be overkill for the current task. Our target trigger (which you will later adjust to suit your system and usage profile), will begin at 20000μs. That means 20,000μs (or 20ms) after our idle max load has been reached, we want to assume idle has been broken and we want to perform an actual task. (We want this value as low as possible without false positives, because it is one of a few factors that determine how snappy and lag free the CPU's response is.)
But at this point we're not ready to take on a full processing load. We may just be briefly scrolling a webpage and don't need the full power of the CPU now that we've allowed it to break out of idle. So we need it to reach a particular frequency and then hold it there again until we're sure the load is justified before we allow it to push the frequency even higher. To do that, rather than just setting
above_highspeed_delay - 20000
we will instead use the format "frequency:delay" to set
above_highspeed_delay - 20000 460000:60000 600000:20000
"Waaaait... What does that do?!"
This tells the Interactive governor to hold out 20ms after our target load when it's at our highspeed_freq (which we're actually using as our idle frequency--not a burst frequency as originally intended), but then it tells the governor to hold for 60ms after it's reached 460Mhz. Once it has exceeded 460Mhz, it then has free reign to scale up without limitation. (This will be optimized with the target_loads setting in a minute. And if you don't know what I'm talking about when I say "highspeed_freq" then you didn't go search for the basic Interactive governor settings and read about it! Go do that before you read any further, because I will not explain the basics of this governor!)
These settings are among the most important, because they limit the phone's clock rates when you are not interacting with it. If it needs to do something in the background, chances are it does not need to run full throttle! Background and idle tasks should be limited to the lowest reasonable clock rate. Generally speaking, if you're just looking at your phone (to read something, for example), you want the phone to use as little CPU power as possible. This includes checking in with Google to report your location or fetching some pull data or... whatever. Things that you don't need performance for.
Optimize Idle Frequency
Now that you've got the base configuration, we need to tweak it so that the CPU stays at your efficient idle frequency (384Mhz in this case) without spontaneously jumping when your phone is actually idle. To do this, open a CPU monitor that displays the current core frequencies (I like CoolTool, but you can use what you like as long as it doesn't significantly impact the CPU use--you're best off using a passive monitor and checking the results after 30-60 seconds of no activity), watch the frequencies and see how often they go above your efficient idle frequency when you're not doing anything at all, and adjust the following:
timer_rate - If your idle frequency is not being exceeded much, adjust this downward in increments of 5000 until it is, then increase it by 5000. If your idle frequency is being exceeded often, adjust this upward in increments of 5000 until your CPU primarily stays at or below your desired idle frequency.
above_highspeed_delay - Only if your timer_rate has matched or exceeded 50000 and still won't stay at or below your desired idle frequency most of the time, set timer_rate to 50000 and adjust the "20000" portion of the value upwards in increments of 5000 until the idle frequency has stabilized.
The lower these two values are, the more snappy/lag free your system will be. So try to get them as low as possible without the idle frequency being exceeded too much, as this inversely affects the snappiness and efficiency of your phone when you're not doing anything. Lower = snappier but uses more CPU when you're not doing anything (such as reading a webpage); higher = less snappy but stays in a power saving state more often reducing CPU use when you're not interacting with the device. These are the most critical in determining your idle power savings, so keep that in mind if you want the most battery life!
Enhance Task Responsiveness
Now use the efficiency and nominal clock rate correlations you made for your master clock rate list in the section above and adjust your frequencies to suit your usage patterns. For example, I had web page scrolling as my 600Mhz rate, so I will open a web page and scroll and see how everything feels. If it feels sluggish, I will increase all the references to "600000" in both above_highspeed_delay and target_loads upwards to the next available clock rate until that task is smooth. What you are looking for is constant poor/sluggish performance when the task you're testing for is using its highest CPU use. If the task becomes sluggish/stuttery as it winds down (such as a scrolling webpage slowing to a stop), we will address that next, so do not take that behavior into consideration as you adjust these values! If the task is smooth until (or after) it slows down, then you have reached your optimal clock rate and can move on.
Find Optimal Loads
Now here's where we get a little math-heavy to determine what the optimal target_load frequencies are for each clock rate. (Might want to bust out a spreadsheet to do the math for you if you're not using a Nexus 5X.)
We want to determine 2 values for every available clock rate: the maximal efficient load and the minimal efficient load. To make this determination, we need to bust out our calculators. (Or spreadsheets!)
For the maximal efficient load, we want to correlate a load value no higher than 90% of a given clock rate before it would be more efficient to jump to the next clock rate–to avoid overwhelming a particular rate while avoiding premature jumps to the next. For this value, we calculate it as:
(clock rate * 0.9) / next highest clock rate
For example, the maximal efficient load for 600Mhz on the Nexus 5X would be caluclated as:
(600000 * 0.9) / 672000 = 80.36% (rounded and normalized: 80)
For the minimal efficient load, we want to correlate a load value at which anything higher would be better served by a higher clock rate. To calculate this:
(1 - next highest clock rate / clock rate) * -1
For example, the minimal efficient load for 600Mhz on the Nexus 5X would be calculated as:
(1 - 672000 / 600000) * -1 = 12.00% (rounded and normalized: 12)
For the Nexus 5X, the maximal efficient loads of CPU 1 are:
384000:75
460000:69
600000:80
672000:76
787000:81
864000:81
960000:69
1248000:78
For the Nexus 5X, the minimal efficient loads of CPU 1 are:
384000:0
460000:19
600000:30
672000:12
787000:17
864000:9
960000:11
1248000:30
1440000:15
For the Nexus 5X, the maximal efficient loads of CPU 2 are:
384000:72
480000:68
633000:74
768000:80
864000:81
960000:69
1248000:83
1344000:84
1440000:84
1536000:84
1632000:86
1689000:83
For the Nexus 5X, the minimal efficient loads of CPU 2 are:
384000:0
480000:25
633000:32
768000:21
864000:13
960000:11
1248000:30
1344000:8
1440000:7
1536000:7
1632000:6
1689000:3
1824000:8
Using Optimal Loads
Now, you might be asking, "Why the heck did I do all this math?! WHAT IS IT GOOD FORRRR????!!!!"
Well, we had put some values into target_loads earlier, but those values weren't arbitrary. See, for all of our nominal clock rates, we want the CPU to hang out on them for as long as possible, provided they're doing the job. For each frequency tagged as our nominal clock rate, we want to use the maximal efficient load in target_loads. For every other frequency, we want to use our minimal efficient load value.
We don't care about those other frequencies. We don't want the CPU to hang out in those states for very long, because it just encourages the device to be reluctant to jump to a higher nominal frequency and causes stuttering. We eliminate the desire for the governor to select those frequencies unless it is absolutely efficient to do so. For all the nominal clock rates, we want the CPU to hang out there... but not for too long! So we set those values to the maximal efficient load, so they can escape to the next nominal frequency before they overwhelm the current frequency.
All said and done, this reduces jitter and lag in the device while providing optimal frequency selection for our day-to-day tasks.
Fix Stuttering
Now that you have adjusted your frequencies for optimal high CPU use in each given task, you may notice some stuttering as the task winds down. (Such as a scrolling webpage slowing to a stop.) If this bothers you, you can tweak this at the expense of some (minor) battery life by adjusting min_sample_time up in increments of 5000 until you are satisfied.
If you have exceeded a value of 100000 for the min_sample_time setting and still are not satisfied, change it back to 40000 and increase (and re-optimize) your idle frequency by one step. This will impact battery life more, but less than if you were to keep increasing the value of min_sample_time.
However, this step should not be necessary if you properly calibrated your maximal and minimal efficient loads!
But What About That 2nd CPU?!
So we've all but ignored the 2nd CPU. The reason? It's a horribly inefficient processor designed for high load tasks that generally don't come into play during normal usage patterns. It's good for gaming and image processing, but not for most moderate tasks a user might employ.
But it is good for one thing that all users do pretty frequently... loading and switching apps.
Fortunately, at least for the Nexus 5X, the system is pretty smart about when to employ the power of this inefficient 2nd CPU. So it's generally kept at bay most of the time. What we want is to configure it to be our burst processor–we want it to come into play spontaneously and quickly during tasks that necessitate immediate high loads, like loading and switching apps. To do this, we will ignore all but 3 frequencies:
384Mhz
1248Mhz
1824Mhz
In this case, we configure it just as we did with CPU 1, but only worry about keeping it idle as much as possible, allow it to jump to 1824Mhz immediately when needed, and encourage it to fall back to 1248Mhz if a sustained load is needed.
These values are ideal for the Nexus 5X, so if you have a different phone, choose the lowest clock rate, highest clock rate, and median efficient clock rate, using the instructions previously.
For the Nexus 5X, we'll jump straight to...
The Money Shot: Part Deux
If you are using a Nexus 5X, use the following Interactive governor settings for CPU 2. ("big"–the one with 2 cores)
(If you are using a phone other than a Nexus 5X, you must read the above sections and replace the frequencies with your own efficient clock rates!)
above_highspeed_delay - 20000
boost - 0
boostpulse_duration - 80000
go_highspeed_load - 99
hispeed_freq - 1824000
min_sample_time - 20000
target_loads - 98 480000:25 633000:32 768000:21 864000:13 960000:11 1248000:95 1344000:8 1440000:7 1536000:7 1632000:6 1689000:3 1824000:95
timer_rate - 20000
timer_slack - 80000
Click to expand...
Click to collapse
SO there you go, that's the gist of it. I got some smaller examples written up later so hopefully it's more understandable.
"I'm Too Lazy To Read All That! WHAT DO I NEED TO DO?!?!"
If you own a Nexus 5X or 6P, install the ElementalX Kernel and the EX Kernel Manager. (Yes, it works in other kernels, but you're on your own regarding how to set the values. Other kernel editors, such as Kernel Adiutor, are currently buggy and problematic, so your mileage may vary. And if you have another device, you must follow the instructions in this post to derive your own values.)
UPDATE: EX Kernel Manager now supports governor profiles and most currently published profiles are distributed with the manager. To access: EXKM> CPU> Governor options> Load, then select the profile you wish to try! Many thanks to @flar2 for providing native support!
ALPHAS – USE AT YOUR OWN RISK!! (Actually, we really like "GostPepper". Try it out. It's spicy! And don't worry–it won't break anything!)
GlassFish (For most devices!) - High battery savings with buttery smooth interface!
HawkTail (6P) - An advanced, modern profile that is both battery efficient and highly performant! All users are urged to check out HawkTail!
Butterfly - A culmination of all strategies, provides smoothest performance of all currently published settings, though battery savings are a little more modest. Excellent for light and moderate users; heavy/marathon users might want to check out a different setting profile.
GhostPepper (6P) - Uses a quantized, frequency-aligned parametric curve to influence low core clock rates while providing extremely smooth transitions from each clock rate and exceptional battery life. The current favorite, albeit not very well tested so far. HIGHLY RECOMMENDED
SilverFish - Effectively eliminates "hispeed_freq" so perceptive scrolling performance is increased, giving the illusion of excellent performance while providing great battery life. Some users experience problems with performance while multitasking--NOT RECOMMENDED FOR EVERYONE. Light users should enjoy this very much, however.
MadDog - The first major departure from the core strategy. Very well tested, extremely stable, and HIGHLY RECOMMENDED if you aren't fully satisfied with v2.0 settings. This is on the table to be the next stable v3.0, so rest assured you can't go wrong with this one!
DrunkSauce - Supreme UI fluidity coupled with excellent active and idle battery drain. Idle Drain was consistently measured to be ~1%. And while I don't rely on SOT figures that people constantly throw around, active drain spanned from 15-20%/hr depending on usage. YMMV. And as always, flawless audio playback for you audiophiles and ARISE users out there.
Those are the ones compiled for now, please remember that these are all up to the users' preference. It will improve YOUR own SOT, not straight up 8 hours on every device. You can copy off the profiles and use your own device frequency and target loads, use an app like Kernel Auditor to help edit them. It works for stock and custom roms too.
Extra credits:
Thanks also to:
Every developer who has seen this guide, modified it, and implemented it.
All the members who contributed and argued about the inner workings of this guide, your constructive feedback is amazing and helped fine-tune future profiles.
To the poisonous and toxic trash member(s) of a certain thread for their lack of help and elitist behaviour. Their embarrassing attitude helps open our eyes to the dos and don'ts of internet manners.
This is for calculating target loads.
Let me give you an example from my Note 1:
My clock rates are (in MHz): 200, 500, 800, 1000, 1200, 1400
Their voltages are (in V): 950, 950, 1050, 1125, 1225, 1300
If I were to plot the differences in voltage, it would appear like this:
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
From the graph, 500MHz to 800MHz has a huge difference in voltage increase compared to 1000MHz to 1200Mhz. That frequency BEFORE the huge jump is the efficient clock rate: 500MHz and 1000MHz.
So, the nominal clock rate on the other hand is the minimum frequency you can use to complete a task (such as watching videos, loading apps, page scrolling). In this case, mine are: 200MHz, 800MHz, 1000MHz
Now, we just calculate (from the first post) the minimal efficient loads for efficient clock rate and maximal efficient loads for nominal clock rate.
That means my target loads will be:
500: 60
800: 72
1000: 75
1200: 17
I skipped the calculations but this will be what it looks like from there. Someone pls do let me know if I made a mistake, as it does tend to confuse people with other devices.
Nominal clock rate: Maximal load
Efficient clock rate: Minimal load
Edit: Those are for the target loads, for the rest of the settings I'll use the profiles'.
Eh, mmight as well reserve this too
Nice looking guide, about to read
wtf,you just copy pasted in the end
Nice beginning, but half is missing, and you are referencing things that haven't been done before
I have some questions regarding the temperature range on my new OPPO Find X2 Neo.
Been searching for info but nothing. Have no idea what a smartphone or tablet CPU or GPU should be for at:
1. idle
2. web browsing ( lite work)
3. heavy gaming ( PUBG, 60fps, HD graphics, 2400x1080p)
I know it depends on the chip itself as different SoC have different rattings but some general numbers are fine. I did try to use Device info HW app but no reading on this
If you want to share, please answer all 3 loads ( if you know)
thanks for your time,
silvagi
Processor Temperature Results for Tens of SoCs -- How Hot is Your Chip?
TestBird has shared with us interesting data of various SoC's heat performance. This was obtained after systematic steps, so hop on over to know more!
www.xda-developers.com
thanks alot for that, according to this article from 2015, idle is 30C and max is 60C.
Do you have more sources of information as the rest of the number are on a link thats no longer working.
NO. GIYF ...
It exist several apps that you can run on an Android device to show you CPU temperature :
How To Show CPU Temperature in Android Status bar
Well, as we all know, Android is always known for its massive app ecosystem. Just take a brief look at the Google Play Store, you will find apps for every
techviral.net
TBH ive tried for days but cant find anything. Anyone else wana share, is very simple info but somehow no info.strange...
i have those app but nothing tell me what the temp ranges are for my Soc ie cpu and gpu, i want know what the max temp is for my soc so i dont cook it
As a safety feature, phones and tablets are designed to shut down in extreme temperatures, AFAIK.