Process & threads - Karmic vs past kernels
peter.matulis at canonical.com
Fri Mar 12 14:17:59 UTC 2010
Chase Douglas wrote:
> On Wed, Mar 10, 2010 at 3:45 PM, Peter Matulis
> <peter.matulis at canonical.com> wrote:
>> Can anyone tell me whether the Karmic kernel has implemented a different
>> way of what it considers a process (as opposed to threads)?
>> I have a situation where CPU load is zero on Karmic but considerably
>> higher in Jaunty and earlier.
>> The scenario is a single java process with many threads. The system has
>> 4 cores and only one java process should logically produce a negligible
>> CPU load but why was this not the case with earlier kernels? Has
>> something changed in Karmic that would explain what I'm seeing?
> I doubt that to be the case. Have you been able to get more data for
> your bug ?
>  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/513848
Yes, but I couldn't get as much CPU usage out of the Karmic test. My
'top' results show the following:
Cpu1 : 0.3%us, 0.6%sy
Cpu2 : 2.4%us, 0.6%sy
Cpu3 : 9.1%us, 1.8%sy
Cpu4 : 16.0%us, 7.4%sy
With a load of 0.00 across the board.
Now since CPU1 has such a low usage it makes sense that load is
negligible since that CPU is always available. It seems that the
question is now:
Why the CPU usage is so much different between Karmic and Jaunty in this
(single process/multiple thread) scenario.
Peter Matulis | GPG 34F740E8
Ubuntu Support Team | Canonical Ltd. (canonical.com)
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