On a new server's CentOS5 install, with nothing in the way of applications running yet, I noticed that the load average was sitting between 2 and 5 all the time, even though top told me CPU was 100% idle.
Eventually I found that stopping the "cpuspeed" subsystem allowed the load average to drop down to near zero, as I would expect it to be.
I have the default /etc/sysconfig/cpuspeed with no customizations.
Is the above behaviour expected? It seems wrong to me. Is cpuspeed broken?
I did notice that with cpuspeed running, the CPUs were running at their minimum frequency of 1.6GHz, and after stopping the cpuspeed service they went up to their maximum speed of 2.8GHz.
The system has a pair of E5660 Xeons, which Linux reports as 24 CPUs!
Cheers Tony
On 05/15/2012 01:05 PM, Tony Mountifield wrote:
Eventually I found that stopping the "cpuspeed" subsystem allowed the load average to drop down to near zero, as I would expect it to be.
and what impact did that have on your power consumption ? And did it make a difference to the performance of the machine ?
In article 4FB3628A.4050300@karan.org, Karanbir Singh mail-lists@karan.org wrote:
On 05/15/2012 01:05 PM, Tony Mountifield wrote:
Eventually I found that stopping the "cpuspeed" subsystem allowed the load average to drop down to near zero, as I would expect it to be.
and what impact did that have on your power consumption ? And did it make a difference to the performance of the machine ?
It's too early to say, since it is a new box that I am just setting up. I would expect it to consume a little more power, since the CPU will be running at full speed, but to perform better.
Since it will be a high-traffic SIP server running Asterisk, I expect running cpuspeed would be a bit pointless anyway.
But that wasn't my main point, which was why cpuspeed should cause an abnormally high load average on this system.
Cheers Tony
On 05/16/2012 09:03 PM, Tony Mountifield wrote:
In article4FB3628A.4050300@karan.org, Karanbir Singhmail-lists@karan.org wrote:
On 05/15/2012 01:05 PM, Tony Mountifield wrote:
Eventually I found that stopping the "cpuspeed" subsystem allowed the load average to drop down to near zero, as I would expect it to be.
and what impact did that have on your power consumption ? And did it make a difference to the performance of the machine ?
It's too early to say, since it is a new box that I am just setting up. I would expect it to consume a little more power, since the CPU will be running at full speed, but to perform better.
Since it will be a high-traffic SIP server running Asterisk, I expect running cpuspeed would be a bit pointless anyway.
But that wasn't my main point, which was why cpuspeed should cause an abnormally high load average on this system.
Cheers Tony
just a thought there is a basic minimum load - when the CPU is at full speed it is a small % - when the CPU is throttled back to 30% of full speed the minimum load is a noticeable %?? HTH
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Karanbir Singh -
Rob Kampen -
tony＠softins.co.uk