powerd effectiveness

Mike Jakubik mikej at rogers.com
Wed Jan 11 16:26:38 PST 2006


It seems that powerd does very little in terms of reducing heat, and 
sacrifices performance while doing so. Am i wrong to assume that 
lowering the cpu's frequency should reduce consumed power, and therefore 
reduce the amount of heat produced? I have tested with mbmon and i see 
no difference between an idle system running with powerd at 75mhz, and 
at full rate without. Also, while testing the speed of a php script, i 
found myself refreshing it quickly in the browser to see the results of 
the timers. I was getting sporadic results, on an otherwise idle system. 
I noticed that if anything cpu intensive ran in the background, my 
script would execute quicker. I disabled powerd and restored the 
frequency, at this point i got more consistent results, and the script 
would execute over 100msec faster. It seems like its not adjusting the 
clock fast enough. Are these problems with powerd or just my hardware? 
It is an old athlon system, running on the via133 chipset .

---
CPU: AMD Athlon(tm) Processor (1210.79-MHz 686-class CPU)
  Origin = "AuthenticAMD"  Id = 0x642  Stepping = 2
  
Features=0x183f9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR>
  AMD Features=0xc0440800<SYSCALL,<b18>,MMX+,3DNow+,3DNow>
real memory  = 536788992 (511 MB)
avail memory = 520237056 (496 MB)
npx0: [FAST]
npx0: <math processor> on motherboard
npx0: INT 16 interface
acpi0: <ASUS A7V> on motherboard
acpi0: Power Button (fixed)
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
acpi_timer0: <24-bit timer at 3.579545MHz> port 0xe408-0xe40b on acpi0
cpu0: <ACPI CPU> on acpi0
acpi_throttle0: <ACPI CPU Throttling> on cpu0
acpi_button0: <Power Button> on acpi0
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
pcib1: <PCI-PCI bridge> at device 1.0 on pci0
pci1: <PCI bus> on pcib1
isab0: <PCI-ISA bridge> at device 4.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <VIA 82C686A UDMA66 controller> port 
0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0xd800-0xd80f at device 4.1 on pc



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