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Old 2006-03-22, 05:09   #1
crash893
 
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Default Would it be possible

Would it be possible to write something that would repleace the "system idle process" with a thread from prime95

i suspect that you would have to use some rootkit like technology to replace the proccess but it seems that it would be too too hard
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Old 2006-03-22, 05:43   #2
moo
 
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um why..... i could easially write a mass deployment script for you but i wouldnt its mine you hear all mine...
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Old 2006-03-22, 06:18   #3
ColdFury
 
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No, the "system idle thread" isn't a process and it usually isn't even a thread either. Its usually just a loop in the scheduler. On Linux for example, all the "idle thread" does is call the cpu halt instruction (on x86) over and over to reduce power consumption. I'd imagine windows does something similar.
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Old 2006-03-22, 07:22   #4
crash893
 
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The way i understood it is that your cpu can not be truly idle it has to be doing something so when there is a gap in work to do System idle proccess feeds the cpu simple work to do (something like 1+1)

i never though if it not being an acutall tread but mabey some one with a little more windows wisdom could chime in

the idea is basicly to replace the kernel proccess that give the cpu the simple work to do with a prime95 thread
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Old 2006-03-22, 08:03   #5
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Actually, it feeds no simple work, but tells the CPU that it can rest now - esp. mobile CPUs indeed decrease its power consumption (lowering voltage and/or frequency).
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Old 2006-03-22, 17:18   #6
ColdFury
 
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Quote:
Originally Posted by crash893
The way i understood it is that your cpu can not be truly idle it has to be doing something so when there is a gap in work to do System idle proccess feeds the cpu simple work to do (something like 1+1)

i never though if it not being an acutall tread but mabey some one with a little more windows wisdom could chime in

the idea is basicly to replace the kernel proccess that give the cpu the simple work to do with a prime95 thread
Yes, the idle thread executes the halt instruction which shuts down the processor for a brief period (actually until a timer interrupt), and reduces power consumption.

To do what you want would require putting the Prime95 code in kernel space. This would be quite tricky, as (at least in Linux) you can't use floating point registers in kernel space.

Moreover, it wouldn't really gain you anything. The idle thread only runs when nothing else is eligible to run. Replacing the idle thread with Prime95 (if you could) is exactly the same as running Prime95.
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Old 2006-03-24, 20:14   #7
cheesehead
 
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Quote:
Originally Posted by ColdFury
Replacing the idle thread with Prime95 (if you could) is exactly the same as running Prime95.
... until one attempts to uninstall it, perhaps.
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