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# "This means that this CPU could have handled all of the work scheduled for the last minute if it were 1.73 times as fast" is also untrue. Load average, once again, is not purely dependent on CPU. That implies that load average only depends on CPU.
--[[User:Grumpyland|-Grumps]] ([[User talk:Grumpyland|talk]]) 06:50, 15 October 2012 (UTC)
== Confusion on Hz definition ==
"On Linux systems, the load-average is not calculated on each clock tick, but driven by a variable value that is based on the Hz frequency setting and tested on each clock tick. (Hz variable is the pulse rate of particular Linux kernel activity. 1Hz is equal to one clock tick; 10ms by default.) Although the Hz value can be configured in some versions of the kernel, it is normally set to 100. The calculation code uses the Hz value to determine the CPU Load calculation frequency. Specifically, the timer.c::calc_load() function will run the algorithm every 5 * Hz, or roughly every five seconds. Following is that function in its entirety:"
The above paragraph in the article is very confusing.
I think it is confusing Hz with the Linux kernel interrupt timer.
>> 1Hz is equal to one clock tick; 10ms by default.
If the definition of hertz is "cycles per second" as defined by the Hertz article on Wikipedia, then how can 1 Hz be 10ms?
1 Hz would be 1 cycle per second, which would mean that the clock ticks once per second.
I think the 10ms is actually referring to the Linux kernel interrupt timer which is normally set to 100, or roughly every 10 ms.
The kernel interrupt will fire 100 times a second.
>> Although the Hz value can be configured in some versions of the kernel, it is normally set to 100.
Huh? I thought it just said that 1 Hz is equal to one clock tick?
I guess that what it is referring to is the Linux timer interrupt frequency again.
>> Specifically, the timer.c::calc_load() function will run the algorithm every 5 * Hz, or roughly every five seconds.
That makes sense if the Hz value is 1 (one cycle per second).
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