I think that it's pretty clear that there really is 5 cores
Source : http://www.nvidia.fr/content/PDF/tegra_white_papers/tegra-whitepaper-0911a.pdf
[DEV] HTC One X firmware | Partitions Info | [20.04.2012]
- Thread starter mike1986.
- Start date
I think that it's pretty clear that there really is 5 cores
Source : http://www.nvidia.fr/content/PDF/tegra_white_papers/tegra-whitepaper-0911a.pdf
I think it's more possible that this 5th core is responsible for events that non of those 4 cores are suppose to take care off. I think it's taking care of low level processes, leaving pure OS to be taken care off by 4 main cores.
That will also explain why cpu0 is online all the time as well.
Screen OFF:
Companion core taking care of low level processes
cpu0 taking care of Android processes while system is in deep sleep state
Screen ON:
Companion core is still taking care of low level processes
cpu0 and cpu1 are online all the time taking care off Android OS
cpu2 and cpu3 are online ad-hoc on heavy load.
That will also explain why cpu0 is online all the time as well.
Screen OFF:
Companion core taking care of low level processes
cpu0 taking care of Android processes while system is in deep sleep state
Screen ON:
Companion core is still taking care of low level processes
cpu0 and cpu1 are online all the time taking care off Android OS
cpu2 and cpu3 are online ad-hoc on heavy load.
From what I understand there, the core we call cpu0 does not really need to always be on. And that would be weird because how would tegra 3 save energy this way...
There must be something we are missing.
Source : http://www.nvidia.fr/content/PDF/te...ecture-for-Low-Power-and-High-Performance.pdf
About lp2 state:
init.endeavoru.common.rc
Also something funny
init.endeavoru.common.rc
Code:
write /sys/module/cpuidle/parameters/lp2_in_idle 1Also something funny
Code:
# Increase read ahead size of mmc block devices from default(128) to [COLOR="Red"]1MB[/COLOR]
# Reduces power comsuption during video playback from sdcards
write /sys/block/mmcblk0/queue/read_ahead_kb [COLOR="red"]2048[/COLOR]
write /sys/block/mmcblk1/queue/read_ahead_kb [COLOR="red"]2048[/COLOR]
Last edited:
it seems that the sasme core pipe is hidden in lg optimus 4x hd as well, since the only four active cores displayed in the debug app is 4 rather than 5, and hence the fifth although active appears to be dormant.
hamdir
Recognized Contributor
i think ill lock my decision for the One X purchase now, simply because im so interested in the Tegra3 concept
seriously out of the box approach, you have to at least give Nvidia that, this will lead to many interesting development scenarios
most reviewers and users of transformer prime confirmed better than expected battery time
its very hard to imagine they went through the trouble of producing a fifth core as well as the yields difficulties for such design, without a good reason, hek they patented the damn thing
we will see
speaking of nvidia....their Kepler GPU is craaaaaaaaaaaazy 1536 unified cuda cores, it makes me cry this will do magic for Mental Ray RT
seriously out of the box approach, you have to at least give Nvidia that, this will lead to many interesting development scenarios
most reviewers and users of transformer prime confirmed better than expected battery time
its very hard to imagine they went through the trouble of producing a fifth core as well as the yields difficulties for such design, without a good reason, hek they patented the damn thing
we will see
speaking of nvidia....their Kepler GPU is craaaaaaaaaaaazy 1536 unified cuda cores, it makes me cry
this will do magic for Mental Ray RT
Last edited:
Isn't this simply an implementation of the big.LITTLE processing concept ARM have been talking about for a while.
A high performance core, even in idle, will draw more power than an energy optimised low performance chip.
The 5th core is almost a sacrificial unit. It is there so you can receive calls, texts, emails and play music at a very low power drain.
When you do anything more taxing it is disconnected and the main CPU cluster takes over.
From memory the main CPU cluster is an A15 and the low power unit an A7.
No matter how much you poke around you won't see both units together as its delt with within the CPU.
EDIT: After posting I find the Arm article, DUH. --> http://www.arm.com/products/processors/technologies/bigLITTLEprocessing.php
A high performance core, even in idle, will draw more power than an energy optimised low performance chip.
The 5th core is almost a sacrificial unit. It is there so you can receive calls, texts, emails and play music at a very low power drain.
When you do anything more taxing it is disconnected and the main CPU cluster takes over.
From memory the main CPU cluster is an A15 and the low power unit an A7.
No matter how much you poke around you won't see both units together as its delt with within the CPU.
EDIT: After posting I find the Arm article, DUH. --> http://www.arm.com/products/processors/technologies/bigLITTLEprocessing.php
Last edited:
great info. glad to see another tegra3 device out now. tegra3 works great on prime. that 5th. companion core barely sips battery juice on standby and low level processes.
to the one person who asked if all 5 cores can be online at once, the answer is no. Nvidia made it this way. they have a patent pending technology on the way it switches cores. low level processes and deep sleep handled by companion core. as soon as a task/app/process demands more power, it instantly switches on the higher powered core or cores.
I have the updated whitepapers on tegra3 and another whitepaper on benefits of multicore mobile CPU. Ill attach them to this post. they are in a zip file since the PDF file size exceeds what xda will let you upload.
hopefully with more developer eyes on tegra3, everyone can benefit. Prime is a great device and I'm sure this HTC phone with tegra3 will be blazing fast. we already hitting 1.7Ghz overclock on prime now. I think someone working on 1.8Ghz. would love to see this reach 2Ghz n be stable and not a major hit on battery(lol).
edit: OP, do you have a transformer prime also? PRIME REVOLUTION ROM
to the one person who asked if all 5 cores can be online at once, the answer is no. Nvidia made it this way. they have a patent pending technology on the way it switches cores. low level processes and deep sleep handled by companion core. as soon as a task/app/process demands more power, it instantly switches on the higher powered core or cores.
I have the updated whitepapers on tegra3 and another whitepaper on benefits of multicore mobile CPU. Ill attach them to this post. they are in a zip file since the PDF file size exceeds what xda will let you upload.
hopefully with more developer eyes on tegra3, everyone can benefit. Prime is a great device and I'm sure this HTC phone with tegra3 will be blazing fast. we already hitting 1.7Ghz overclock on prime now. I think someone working on 1.8Ghz. would love to see this reach 2Ghz n be stable and not a major hit on battery(lol).
edit: OP, do you have a transformer prime also? PRIME REVOLUTION ROM
Last edited:
wikipedia describes it pretty well:
http://en.wikipedia.org/wiki/Tegra
i guess the companion core does the SMP scheduling and presents the other cores virtually to the OS, and there is no need for the OS to know about the companion core
http://en.wikipedia.org/wiki/Tegra
i guess the companion core does the SMP scheduling and presents the other cores virtually to the OS, and there is no need for the OS to know about the companion core
Interesting to see NVidias take on low power. Different from Qualcomms but along the same lines as the ARM road map.
With Qualcomms dual core chip in the Sensation in low activity mode the second core is like a USB memory stick, when its not needed it is completely removed from the system.
NVidia are closer to ARM in having a low power core for menial tasks the is switched out when demand rises.
Not sure how they can keep a patent on this with ARM implementing it on future processors unless it is limited to A9 and ARM are opening up A15 -> A7.
Regardless I want one to play with.
With Qualcomms dual core chip in the Sensation in low activity mode the second core is like a USB memory stick, when its not needed it is completely removed from the system.
NVidia are closer to ARM in having a low power core for menial tasks the is switched out when demand rises.
Not sure how they can keep a patent on this with ARM implementing it on future processors unless it is limited to A9 and ARM are opening up A15 -> A7.
Regardless I want one to play with.
I think since the 5th core seamlessly takes over and is invisible to the OS it will probably just read as CPU0 (just an idea)
Maybe we should split this discussion into a new thread, think Mike's OP has been well and truely highjacked
I too am really interested in tegra 3 technology and excited to see how it develops. Might have to upgrade my Xoom to a Prime as well
Maybe we should split this discussion into a new thread, think Mike's OP has been well and truely highjacked
I too am really interested in tegra 3 technology and excited to see how it develops. Might have to upgrade my Xoom to a Prime as well
Since the companion core is only active during standby, would too many background tasks such as sync or apps like task panel causes your phone to be not sleeping in the companion core state??
I believe there is a benchmark for it to fully utilise the companion core, so how could we control our uses so we can make the best out of the battery life?
Sent from my Desire HD using XDA
I believe there is a benchmark for it to fully utilise the companion core, so how could we control our uses so we can make the best out of the battery life?
Sent from my Desire HD using XDA
Not really, symlink /system/vendor /vendor is common for all Android ICS devices.
OKay, I just got my One X and it is by far the best device I´ve ever owned so far !
But I dropped by to tell you guys that my HBOOT version is 0.43.xxxx can´t remember exactly at the moment. Does that might help for a S-OFF unlock ?
Greetz Designator!
But I dropped by to tell you guys that my HBOOT version is 0.43.xxxx can´t remember exactly at the moment. Does that might help for a S-OFF unlock ?
Greetz Designator!
51000 | 102000 | 204000 | 340000 | 475000 | 640000 | 760000 | 880000 | 1000000 | 1100000 | 1200000 | 1300000
So the max freq is 1.3G?
So the max freq is 1.3G?
Similar threads
Top Liked Posts
-
There are no posts matching your filters.
-
38This thread's content might brick your device.
This is not a ROM thread, so I'm not going to answer again and again and again the same questions over and over and over again.
You can't read - quit this thread now. You can read but you can't understand more or less simple things - quit as well.
You can read and you understand things, but you are too lazy to read the whole thread before asking the question - watch this first. And quit.
This is what we know so far:
Some conclusions:
1. It's very nice to see that finally someone separated "internal sd card" from userdata partition. So it's no longer linked to /data/media, as it used to be on Asus Transformer, Transformer Prime, Galaxy Nexus etc. but it's a separate partition now - mmcblk0p14. Basically the biggest benefit from that is that now formatting userdata partition will no longer erase virtual sd card content.
2. It seems that NFC and WLAN deep settings are stored on separate partitions: mmcblk0p1 (wlan) and ? (NFC).
3. There is a 5th PHYSICAL core, but it's invisible to the system. Android only sees the 4 main cores. The 5th companion core is not controlled by Android. Tegra 3 architecture itself handles the load balancing between the main cores and the companion core. (Thanks to Diamondback)
4. There is no radio.img in current RUUs.
Please post here your findings, thoughts or experience with after flashing images listed above.11Here are some details about CPU kernel settings:
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
51000 | 102000 | 204000 | 340000 | 475000 | 640000 | 760000 | 880000 | 1000000 | 1100000 | 1200000 | 1400000 | 1500000
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
interactive conservative ondemand powersave userspace performance
Some details about how Tegra 3 works on HTC One X:
1. While screen is turned OFF only cpu0 is online. cpu1, cpu2 and cpu3 are all offline.
2. I think that cpu2 and cpu3 are online only on heavy load. That needs to be confirmed.
3. While screen is turned OFF only interactive governor is available.
4. When battery is < 20%, CPU downclocks to 1.0 GHz.
Fastboot commands that doesn't work without S-OFF:
- fastboot flash rcdata rcdata.img
- fastboot oem writesecureflag
- fastboot oem writecid
9
No that is wrong. There is a fith PHYSICAL core but it's invisble to the system. Android only sees the four main cores.
The fith companion core is NOT, i repeat NOT, controlled by android. The tegra architecture itself handels to load balacing between the main cores and the companion core.
YOu won't find any traces of this companion core in the system.3
Kernel, recovery, etc... Though I was disapppointed to see that 2.6.3x kernel was used by HTC...
Sent from my HTC One X using XDA2
would you have really s-off then you wouldn't have orang cid ....pls post a photo of you "s-offed" phone
