Machine slow

[Steen, Glenn]

Billy A. Pumphrey wrote:
> Quick verification on load average if I may.
> 
> I do not understand how those numbers work.  They appear not to be
> percent usage.
> 
> How do the load average numbers work?
> On my mailwatch, my usually is around .60-1.4
> 
> Billy Pumphrey
> IT Manager
> Wooden & McLaughlin
> 
(snip)

The "load factors" are perhaps the most abused "performance statistics"
around... They're just the CPU run queue size (+ running jobs) averages
calculated for 1, 5 and 15 minutes. Nice to know and a quick indicator,
but nothing else.

For example: on a one CPU system a load of 2 might be less than
desirable,
while on a system with 4 CPUs it shows two CPUs idling away... So one
needs weigh the system as a whole when determining if a certain load is
fine or not.

If you're on Linux or Solaris I'd recommend the very goo Swordfish book
from o'reilly (System Perfomance Tuning). An excellent read.

-- Glenn

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