Re: Top command issue in kernel 2.6.16 and some kernel 2.4.16

"karnan" <s_karnan@xxxxxxxxx> writes:

We have our application in user space and driver in kernel space.
There is block read to get the data from kernel space to user space.
When we use Top command to measure it show 0% for 60 seconds and 99%
for 30 seconds and it repeats. But my code should always take about
30% of CPU all the time because this works based on real time data
available from kernel driver. Can anybody help to understand why top
is showing 0% while I know that app should take about 30%. why is
showing 99%? Is there any area I need to look at for this 99%
occupancy?

We tested in both kernel 2.6 and 2.4. This issue happens in all
platform for kernel 2.6. In case of kernel 2.4, this happens only in
one platform. In other platform, tops shows correctly 30% all the
time.

Could anybody explain what could wrong here?

http://news.gmane.org/find-root.php?group=gmane.linux.kernel&article=492270
(esp. first reply)

Contains some information on why you might notice strange top(1) behavior.

--
vale
.

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