4.2BSD loadav() routine

[Mahler]

Below is an abstract for a very brief paper.  4.2 BSD sites might want to
consider changing to this new load averaging routine for calculating the
loadav numbers.  The loadav is still based on the number of jobs in the
run queue (we are talking about changing that too ... ), but this routine
performs a true mathmatical average of the load.

Electronic copies of the paper, including source code (its small), will
be mailed to system adminstrators on request.
Reply directly to ...!pur-ee!mahler


       A New Load Average Algorithm for 4.2 BSD UNIX*


                     William R. Simmons
                     Stephen J. Mahler
                       David A. Curry

                Engineering Computer Network
              School of Electrical Engineering
                     Purdue University
               West Lafayette, Indiana 47907

                          ABSTRACT

          This paper describes briefly a direct  method
     of computing VAX 4.2BSD UNIX System load averages.
     The load average algorithm supplied with  4.2  BSD
     UNIX  uses an approximation algorithm to calculate
     its values.  While the approximation is reasonable
     in  some computing environments, its error is sig-
     nificant under rapidly changing  load  conditions.
     The  direct  method  presented  here  provides the
     actual  load  averages  for  the  prescribed  time
     intervals.  Such values allow much more definitive
     use and interpretation by system and user programs
     making decisions based on system load.


June 1984
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* UNIX is a trademark of Bell Laboratories.