system/powernowd: Updated for version 1.00

1 files changed, 53 insertions, 8 deletions

diff --git a/system/powernowd/README b/system/powernowd/README
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+Overview:
 This is a very simple program that will adjust the speed of your CPU
 depending on system load.  It works as a client of the CPUFreq driver.
-It is designed for use with CPU's supporting AMD's PowerNow power
-management scheme, as it's algorithm works better if there are more
-than two CPU speeds available.  (aka, ARM, AMD K6/K7, Via C3, and
-Crusoe as opposed to traditional Intel and Ultrasparc).
+It is designed for use with CPU's supporting AMD's PowerNow power management
+scheme, as it's algorithm works better if there are more then two CPU
+speeds available.  (aka, ARM, AMD K6/K7, Via C3, and Crusoe as opposed to
+traditional Intel and Ultrasparc).
 
-Powernowd uses the userspace governor, which is included in the Slackware
-kernel images.
+This program is essentially a simple client to the CPUFreq sysfs interface.
+This means that you -need- to be running Linux v2.5 or later that includes
+the sysfs interface.  This daemon will -not- work with the CPUFreq driver
+interface included in Linux v2.4.  Feel free to write your own daemon
+to support that if you like; you can even use this as a starting point.
+If there's enough clamoring for it, then maybe I'll whip up something.
+You also need a CPU that supports frequency scaling and supports the CPUFreq
+interface.  This code has been tested on various AMD and PPC processors
 
-It is not wise to run two concurrent cpu frequency adjusting programs,
-for example, cpufreqd and powernowd simultaneously.
+I have been running this daemon on my AMD laptop for over 2 years with no
+problems to report, and it's nice that my laptop remains cool unless I'm
+really doing something intensive, like watching DivX movies, without me
+having to manually intervene and set the speed. I just recently bought an
+Apple iBook G3, and powernowd-0.80 worked flawlessly on it right out of
+the box.
+
+
+Features:
+
+This daemon's goal is simplicity and speed.  It doesn't try and make
+too many decisions for you.  That's its beauty, but it may not be what
+everyone's looking for. Some of the features this daemon has:
+
+One, simple heuristic to determine CPU load: "user + sys" time.
+Ignore "niced" programs (setiathome, itself, etc). In my mind this is
+consistent with what is meant when someone 'nice's a program to begin
+with. (configurable in v0.85+) Designed for CPU's that support more
+then two speed states, but works well with anything.  Very fast, low
+overhead /proc/stat gathering (method stolen from procps).  Supports SMP
+Will automatically switch to 'userspace' governor.  Care taken to make
+the code non-root exploitable (but please audit for yourself first!)
+Frequency step size is configurable (default to 100MHz/step) 4 different
+behavioral modes to choose from (SINE, AGGRESSIVE, PASSIVE, LEAPS),
+which determine the behavior when the load changes. Configurable from the
+command line.  Written in C for speed and simplicity.  Logging to stdout
+or syslog Configurable Polling frequency in milliseconds (defaults to 1s)
+Configurable highwater/lowwater marks for CPU usage. (defaults 80/20%)
+
+Many similar daemons use other methods to determine what speed to use,
+such as battery status, AC status, temperature, fan status, etc. They all
+have their place.  I however feel that in the grand scheme of things none
+of the above matters. When I'm not using my CPU, I don't care if it's
+running at a slower speed. When I -am- using my CPU, I only need it to
+be fast enough to handle the task at hand without hiccuping. And when I'm
+taxing my CPU, I want it running full speed. That's all this daemon does,
+monitor CPU load and adjust the speed accordingly.  Since in all reality
+my CPU is idle 99% of the time (or playing mp3's which it can easily do
+at it's lowest speed rating), this by definition leads to low power usage,
+low temperatures, low speed fans, and better battery life.