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Re: Use of Swap Space

On 02/02/2009 11:34 AM, Douglas A. Tutty wrote:
On Fri, Jan 30, 2009 at 10:04:19PM -0600, Ron Johnson wrote:
On 01/30/2009 09:54 PM, Douglas A. Tutty wrote:
On Sat, Jan 31, 2009 at 02:52:34AM +0000, Tzafrir Cohen wrote:
On Sat, Jan 31, 2009 at 12:54:34AM +0000, Dean Chester wrote:

If a 100% CPU usage causes your computer to *over*heat (which is
something you did not write above) you'll have a problem elsewhere (e.g.
a dist-upgrade that includes tex-live :-) )
Or, is the board firmware slowing down the CPU to allow it to cool,
which makes a basically idling debian system to use a higher percentage
of available CPU (less idle time).  Remember, its a percentage of CPU
capacity.  If the CPU slows down, the the available capacity decreases.
But "100% CPU usage" isn't the same as "running at 100% of rated clock speed".

Is *that* what you are really referring to?

To illustrate what I mean, lets change from percentage to some
ficticuous numbers.  Lets say that the CPU when cool can make 100
BIGMACS per second.  When the CPU is cool, top shows that it is 99% idle
(1% CPU usage), so it takes 1 BIGMACS per second to keep the system and
top running.  Now, heat up the CPU too far and the BIOS slows down the
CPU to make it run cooler.  Now the CPU can only make 1 BIGMACS per
second.  It still takes 1 BIGMACS per second to keep the system and top
running, so now top will show that the CPU is 0% idle (100% CPU usage).

This is what I was suggesting.

No need for analogies.

$ cat /proc/cpuinfo | grep 'cpu MHz'
cpu MHz		: 1000.000
cpu MHz		: 1000.000

[Do something CPU-intensive.]

$ cat /proc/cpuinfo | grep 'cpu MHz'
cpu MHz		: 2100.000
cpu MHz		: 2100.000

Again, I ask if you are referring to clock speed or CPU usage?

Ron Johnson, Jr.
Jefferson LA  USA

"I am not surprised, for we live long and are celebrated poopers."

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