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Question regarding total amount of active CPU cores..

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Destroyedbeauty
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Default Question regarding total amount of active CPU cores..

I did some checking in the .sh files, inside the /system/etc folder, and found inside the set_governor.sh that the Z1 is pre-configured to keeping all 4 CPU cores online at the same time. For performance reasons it seems..

Should I delete every line that is related to total amount of online / active cores so the kernel can decide and take care about that by itself or should I echo 0 the amount of cores that I want to be in sleep / idle mode?

I am tweaking my brand new Z1 for even more battery life, that's why I am asking this question!

 
tomascus
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Originally Posted by Destroyedbeauty View Post
I did some checking in the .sh files, inside the /system/etc folder, and found inside the set_governor.sh that the Z1 is pre-configured to keeping all 4 CPU cores online at the same time. For performance reasons it seems..

Should I delete every line that is related to total amount of online / active cores so the kernel can decide and take care about that by itself or should I echo 0 the amount of cores that I want to be in sleep / idle mode?

I am tweaking my brand new Z1 for even more battery life, that's why I am asking this question!

All four cores are not online at the same time all the time. At idle, only 1 core is active at min frequency 300 mhz, the other cores come online when there is demand for them. Disabling cores has never helped improve battery life in my experience, merely causing slow downs and resulting in the CPU taking longer to complete processing, using up precious power before it's able to return to min frequency.

(My limited knowledge)
 
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All four cores are not online at the same time all the time. At idle, only 1 core is active at min frequency 300 mhz, the other cores come online when there is demand for them. Disabling cores has never helped improve battery life in my experience, merely causing slow downs and resulting in the CPU taking longer to complete processing, using up precious power before it's able to return to min frequency.

(My limited knowledge)
If this is the case - why does kernel modules like ECO-Mode exist that shuts down two cores and converts the phone into an DC one?

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Android Devices that I am using:
1. Sony Xperia Z1 - ROM: RomAur v9.1 / Kernel: Unofficial Doomkernel v21 with 4.4.4 support
2. Sony Xperia Tablet Z - ROM: Stock 10.5.A.0.230 / Kernel: UnleaZhed XTZ v0.2
 
tomascus
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(Last edited by tomascus; 11th January 2014 at 02:24 PM.)
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Originally Posted by Destroyedbeauty View Post
If this is the case - why does kernel modules like ECO-Mode exist that shuts down two cores and converts the phone into an DC one?

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Eco mode? Never heard of it. Don't know anything that makes the Xperia Z1 go dualcore mode, might want to show me a link?

Ps. Tried underclocking with fauxclock or trickstermod?

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McT1980
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Why would anyone want to lower speed or nr of cores active on a beast like this? Go buy an older phone if u want a slower one lol. It uses the power it needs to complete the tasks it is asked to do unless u got some crap laying in the background draining your battery that way.
 
eclyptos
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Why would anyone want to lower speed or nr of cores active on a beast like this? Go buy an older phone if u want a slower one lol. It uses the power it needs to complete the tasks it is asked to do unless u got some crap laying in the background draining your battery that way.
This have nothing to do with get a slow device. This probably will help avoid battery drain and without a few test no body can said it will not work.
 
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This have nothing to do with get a slow device. This probably will help avoid battery drain and without a few test no body can said it will not work.
What battery drain are you referring to? When people talk about battery drain they usually mean when screen is of and they usually got some crap running in the background. I can get 2-3 days of moderate usage running dooms kernel and that's not bad.
 
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What battery drain are you referring to? When people talk about battery drain they usually mean when screen is of and they usually got some crap running in the background. I can get 2-3 days of moderate usage running dooms kernel and that's not bad.
Any core need energy, trying to switch them off when not needed can only improve battery standby. This is not the solution for the battery, this is one of many. We know that the crap running in background it's another reason and the screen too. Here we considering only the CPU.
 
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Any core need energy, trying to switch them off when not needed can only improve battery standby. This is not the solution for the battery, this is one of many. We know that the crap running in background it's another reason and the screen too. Here we considering only the CPU.
Agreed, but it would surprise me if the phone runs at 4x300mhz when the screen is of. 1 core is enough and i've seen several posts saying that it runs with 1 when the screen is of. If it runs at 4 however,yeah you could save some juice by disabling cores.

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