Re: New Metrics to measure Load average

[Shailabh Nagar <nagar@watson.ibm.com>]

sena seneviratne wrote:

> In fact my question in the post was about performance testing after 
> the changes being done.
>
> --2) Now about the tests
> --As I have documented all this yet need to perform some standard 
> tests for the sake of completion.
> --What tests should I carry out to prove that the system is still intact?


> --Please tell me whether the below is correct?
>
> --(a) As suggested by the http://kernel-perf.sourceforge.net/ the 
> lmbench and re-aim-7 test packages can be used to test the 
> ----performance of the kernel before making changes and after. (Not 
> done as yet)
>
To measure impact of patches for a kernel tree, Contest (available from 
http://freshmeat.net/projects/contest/)
is a good start. lmbench is also useful.

> --(-b) Further tests have been carried out to check the response time 
> of short tasks before making changes and after making --changes. The 
> results indicated that there was no difference in the response time 
> after introducing the changes to the kernel (done)
>
> ---(c) Thereafter the tests have been carried out to check the runtime 
> of long tasks before and after making changes. The results of the 
> tests revealed that there is no change in reported runtime in both 
> occasions.(done)
>
Why is there a distinction between short and long running tasks when 
overall performance overhead
of the kernel needs to be verified ?