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== Waiting, states, calculations ==
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Optimum load average should be the same as the number of processors (or in case of hyperthreading, virtual processors). ie not 2 for a dual processor sysem, 4 for a dual processor with hyper etc...
<small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Mchicago|Mchicago]] ([[User talk:Mchicago|talk]] • [[Special:Contributions/Mchicago|contribs]]) 19:08, 27 February 2006</span></small><!-- Template:Unsigned -->
A clearer, more detailed, and authoritative explanation of waiting, states, and calculation (including analysis of the operating system code) can be found in the reference listed under External Links (http://www.teamquest.com/resources/gunther/display/5/index.htm). Anyone contemplating changes to this section (I lack the necessary detailed knowledge) should take a close look at that reference.
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== Instantaneous percentage of CPU utilization on Windows?!? ==
The author states that "On Microsoft Windows PC systems, the system load is given as an instantaneous percentage of CPU utilization." That's not possible, there is no CPU "speedometer" on any processor chip set that I know of. An operating system can only recognize two basic states: idle (0% utilization) or not idle (100% utilization). To report a utilization between 0% and 100% requires that it average the two basic states over some time period. Most operating systems do this by sampling the current state during each clock interrupt and incrementing one of the two state counters (most operating systems also have sub-counters under Not Idle such as Wait I/O in UNIX or processing nested interrupts). The utilization that is then reported is the difference between the counters over some sampling interval divided by the total samples during the interval and that is what is reported as utilization. As for what time interval Windows utilities such as perfmon and the Logs & Alerts Service use I have no clue.
* Some chips scale frequency now, but your point is still 99% correct. [[User:128.135.99.80|128.135.99.80]] 19:57, 7 September 2006 (UTC)
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It's like measuring speed from an erratically moving car.
If that is to be fixed, it would have to somehow poll the frequency that the cpu is running at.
<small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:70.54.202.152|70.54.202.152]] ([[User talk:70.54.202.152|talk]] • [[Special:Contributions/70.54.202.152|contribs]]) 13:03, 1 November 2006</span></small><!-- Template:Unsigned -->
:I suspect part of the problem is that the term "load average" is very well defined, but the term "load" is vague at best. This article is currently mostly about the Unix load average, and ''not'' about "Load (computing)". Whether we should change this article to be more general, or simply rename it to [[Load average]] and create a new [[Load (computing)]] stub with the rest of the content, I dunno. --[[User:DragonHawk|DragonHawk]] 02:06, 4 January 2007 (UTC)
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== Processes or jobs? ==
The article talks about "each process that is using CPU". I think it's more common to talk about "each job", which isn't necessarily synonymous. For example, a process with two threads can count as two jobs.
:I think the problem is that each UNIXoid operating system will use different terms. For example, on Linux your jobs are called "tasks".
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it referred to a batch file containing some non-interactive stuff to be done in a certain sequence (series or parallel or both).
A job usually contains more processes and has nothing to do with the load average we are talking about here.
<small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:70.54.202.152|70.54.202.152]] ([[User talk:70.54.202.152|talk]] • [[Special:Contributions/70.54.202.152|contribs]]) 13:07, 1 November 2006</span></small><!-- Template:Unsigned -->
For unix, there are specific meanings to the terms "job" and "process". A job is in the jobtable, a process is in the process table. See `jobs` for a list of jobs for the current terminal, and `ps` for a list of process for the current system. Don't be confused by cron terminology; jobs aren't processes. --[[Special:Contributions/87.194.236.208|87.194.236.208]] ([[User talk:87.194.236.208|talk]]) 15:20, 4 May 2008 (UTC)
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I also remember seeing the Load Average used on TOPS20 before seeing it on BSD Unix.
-HWM <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:TenexHacker|TenexHacker]] ([[User talk:TenexHacker|talk]] • [[Special:Contributions/TenexHacker|contribs]]) 03:38, 3 September 2006</span></small><!-- Template:Unsigned -->
== Error in example of load average? ==
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To me, a load of 2.00 would mean that it's '''over'''loaded by 100%, not 200%.
<small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Vmardian|Vmardian]] ([[User talk:Vmardian|talk]] • [[Special:Contributions/Vmardian|contribs]]) 13:25, 21 November 2006</span></small><!-- Template:Unsigned -->
:The author did OK until they said "For example a load average of "3.73 7.98 0.50" on a single CPU system can be interpreted as:
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