cpuspeed

CPUSPEED(8)		       Program Options			  CPUSPEED(8)



NAME
       cpuspeed - user-space cpu frequency scaling program, v1.2.1

SYNOPSIS
       cpuspeed [Options]

DESCRIPTION
       cpuspeed v1.2.1

       This  program  monitors	the  system’s  idle percentage and reduces or
       raises the CPUs’ clock speeds and  voltages  accordingly	 to  minimize
       power  consumption  when	 idle  and  maximize performance when needed.
       This is the default.

       The program may also optionally be  configured  to  reduce  the	CPUs’
       clock  speeds  if  the  temperature  gets too high, NOT minimize their
       speeds if the computer’s AC adapter is disconnected or maximize	their
       speeds when the AC adapter is connected.

       By default this program will manage every CPU found in the system.

	      Options:

       -d

	      Tells the process to daemonize itself (run in background).

       -i <interval>

	      Sets  the	 interval  between idle percentage tests and possible
	      speed changes in tenths of a second (default is 20).

       -p <fast up> <threshold>

       Sets the CPU idle percentage thresholds.
	      <fast up> is the idle

	      percentage below which a CPU will be set to the highest  possi-
	      ble  speed.   <threshold>	 is the idle percentage above which a
	      CPU’s speed will be decreased and below  which  a	 CPU’s	speed
	      will be increased (defaults are 10 and 25).

       -m <minimum speed>

	      Sets  the	 minimum  speed	 in KHz below which a CPU will not be
	      set.

       -M <maximum speed>

	      Sets the maximum speed in KHz above which a  CPU	will  not  be
	      set.

       -t <temp file> <maxtemp>

	      Sets  the	 ACPI  temperature  file and the temperature at which
	      CPUs will be set to minimum speed.

       -T <interval>

	      Sets the interval at which the temperature will  be  polled  in
	      tenths  of a second (default is 10).  (Requires the ’-t’ option
	      above.)

       -a <AC file>

	      Sets the ACPI AC adapter state file and tells  the  program  to
	      set  the	CPUs  to minimum speed when the AC adapter is discon-
	      nected.  (This is the default but is  changeable	by  the	 ’-D’
	      option below).

       -A <interval>

	      Sets  the interval at which the AC adapter state will be polled
	      in tenths	 of a second (default is  50).	 (Requires  the	 ’-a’
	      option above.)

       -C

	      Run  at  maximum speed when AC adapter is connected.  (Requires
	      the ’-a’ option above.)

       -D

	      Do NOT force minimum speed when  AC  adapter  is	disconnected.
	      (Requires the ’-a’ option above.)

       -r

	      Restores previous speed on program exit.

       -s <CPU>

       Manage only a single CPU.
	      <CPU> specifies the number of the CPU

	      to  manage and is in the range 0 to (n-1) where ’n’ is the num-
	      ber of CPUs in the system.  Without  this	 option	 the  program
	      creates copies of itself to manage every CPU in the system.

	      To  have a CPU stay at the highest clock speed to maximize per-
	      formance send the process controlling that CPU the SIGUSR1 sig-
	      nal.

	      To  have	a CPU stay at the lowest clock speed to maximize bat-
	      tery life send the process controlling  that  CPU	 the  SIGUSR2
	      signal.

	      To  resume  having  a CPU’s clock speed dynamically scaled send
	      the process controlling that CPU the SIGHUP signal.

SEE ALSO
       The CPUSpeed web page:
	  http://carlthompson.net/Software/CPUSpeed

LICENSE
       CPUSpeed is released under the GNU General Public  License  version  2
       (or  if	you  wish any later version). This license allows you to use,
       copy, distribute and modify the software with very  few	restrictions.
       The full text of the license may be found here:
	 http://carlthompson.net/Software/CPUSpeed/License

AUTHOR(S):
       Carl Thompson - cet [at] carlthompson.net
		  (copyright 2002 - 2005)



cpuspeed v1.2.1		       January 09, 2005			  CPUSPEED(8)