topic Top - Load Average in Operating System - HP-UX

Top - Load Average

Faizer — Mon, 02 Oct 2006 01:25:22 GMT

Dear All,

Load averages: 0.42, 0.36, 0.32
455 processes: 365 sleeping, 89 running, 1 zombie
Cpu states:
CPU LOAD USER NICE SYS IDLE BLOCK
0 0.49 0.0% 10.3% 3.6% 86.1% 0.0%
1 0.31 0.4% 2.2% 2.0% 95.4% 0.0
2 0.63 0.6% 2.6% 2.0% 94.8% 0.0
3 0.25 0.0% 3.2% 2.8% 94.0% 0.0 - ----- ----- ----- ----- ----- ----- avg 0.42 0.2% 4.6% 2.6% 92.6%

Memory: 3540388K (1924328K) real, 16936928K (4724336K) virtual, 78584K free Pag
e# 1/51

The above is an output of top. Please can someone explain to me 'The load average, what it means and what determines this Load average and how does this effect the system.

Thanking you in advance
Faizer

Re: Top - Load Average

Murat SULUHAN — Mon, 02 Oct 2006 01:42:38 GMT

Hi Faizer

Please check this url

http://www.teamquest.com/resources/gunther/display/5/index.htm

Best Regards
Murat

Re: Top - Load Average

Henk Geurts — Mon, 02 Oct 2006 02:01:47 GMT

hi Faizer.
The load averages are of last 1, 5 & 15 minutes (in that order) ...and are based on processor load.

Re: Top - Load Average

Faizer — Mon, 02 Oct 2006 02:44:37 GMT

Thanku all
The link to the document gives me the substance that I require.
Its a good document.
Thanks a lot for your time
Cheers
Have a great day.
Faizer

Re: Top - Load Average

Bill Hassell — Mon, 02 Oct 2006 17:09:32 GMT

The referenced web page may a bit too confusing. The load average is a measure of the run queue, which is all the processes that are running or ready to run. In a simplistic one processor system, 1 process that uses 100% of the CPU represents a run queue of 1 or a load average of 1.0. If two processes consume 100% CPU time, both are queued to run but only one runs at any instant. By timesharing, each process gets a short time to run and the load factor (run queue) is 2.0.

Now when you have multiple processors, the load factor will be correspondingly higher. A 4 processor system is not 100% loaded until the load factor is 4.0 (4 processes each taking 100% CPU time).

Now a load factor that is higher than the number of CPUs is not necessarily a problem. It is only one metric used in looking at a system's performance.