driver or calculation of load average wrong ?

driver or calculation of load average wrong ?

[Frank Salomon]

Hello All,

I have the following configuration:
- CentOS 5
- kernel 2.6.20.1
- My own driver in a kernel_thread:
		while ( 1 ){
			printk ( KERN_INFO "go sleep, %lu\n", jiffies );
			current -> state = TASK_UNINTERRUPTIBLE;
			schedule_timeout ( msecs_to_jiffies(4000) );
			printk ( KERN_INFO "wakeup, %lu\n", jiffies );
		}

Each time I load the driver, the load average in /proc/loadavg reached:
	$ cat /proc/loadavg
	0.99 0.62 0.26 1/47 2868
Without my driver:
	$ cat /proc/loadavg
	0.03 0.03 0.00 1/47 2867

I changed nr_active(void) in kernel/sched.c:
unsigned long nr_active(void)
{
         unsigned long i, running = 0, uninterruptible = 0;

         for_each_online_cpu(i) {
                 running += cpu_rq(i)->nr_running;
                 uninterruptible += cpu_rq(i)->nr_uninterruptible;
         }

         if (unlikely((long)uninterruptible < 0))
                 uninterruptible = 0;

// original:     return running + uninterruptible;
         return running;
}

Driver loaded or not:
	$ cat /proc/loadavg
	0.03 0.03 0.00 1/47 2867

Any help or comments would be really great?

Best regards, thanks, Frank




WINCOR NIXDORF International GmbH
Sitz der Gesellschaft: Paderborn
Registergericht Paderborn HRB 3507
Geschäftsführer: Eckard Heidloff (Vorsitzender), Stefan Auerbach, Dr. Jürgen Wunram
Vorsitzender des Aufsichtsrats: Karl-Heinz Stiller
Steuernummer: 339/5884/0020 - Ust-ID Nr.: DE812927716 - WEEE-Reg.-Nr. DE44477193

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driver or calculation of load average wrong ?

[Frank Salomon]

Hello All,

I have the following configuration:
- CentOS 5
- kernel 2.6.20.1
- My own driver in a kernel_thread:
		while ( 1 ){
			printk ( KERN_INFO "go sleep, %lu\n", jiffies );
			current -> state = TASK_UNINTERRUPTIBLE;
			schedule_timeout ( msecs_to_jiffies(4000) );
			printk ( KERN_INFO "wakeup, %lu\n", jiffies );
		}

Each time I load the driver, the load average in /proc/loadavg reached:
	$ cat /proc/loadavg
	0.99 0.62 0.26 1/47 2868
Without my driver:
	$ cat /proc/loadavg
	0.03 0.03 0.00 1/47 2867

I changed nr_active(void) in kernel/sched.c:
unsigned long nr_active(void)
{
          unsigned long i, running = 0, uninterruptible = 0;

          for_each_online_cpu(i) {
                  running += cpu_rq(i)->nr_running;
                  uninterruptible += cpu_rq(i)->nr_uninterruptible;
          }

          if (unlikely((long)uninterruptible < 0))
                  uninterruptible = 0;

// original:     return running + uninterruptible;
          return running;
}

Driver loaded or not:
	$ cat /proc/loadavg
	0.03 0.03 0.00 1/47 2867

Any help or comments would be really great?

Best regards, thanks, Frank
-- 
WINCOR NIXDORF International GmbH
Retail Store Solutions
Heinz-Nixdorf-Ring 1
33106 Paderborn
Tel. +49 (0) 30 5017 1335
Fax +49 (0) 30 5017 1305
mail frank.salomon@wincor-nixdorf.com


WINCOR NIXDORF International GmbH
Sitz der Gesellschaft: Paderborn
Registergericht Paderborn HRB 3507
Geschäftsführer: Eckard Heidloff (Vorsitzender), Stefan Auerbach, Dr. Jürgen Wunram
Vorsitzender des Aufsichtsrats: Karl-Heinz Stiller
Steuernummer: 339/5884/0020 - Ust-ID Nr.: DE812927716 - WEEE-Reg.-Nr. DE44477193

Diese E-Mail enthält vertrauliche Informationen.
Wenn Sie nicht der richtige Adressat sind oder diese E-Mail irrtümlich erhalten haben,
informieren Sie bitte sofort den Absender und vernichten Sie diese E-Mail.
Das unerlaubte Kopieren sowie die unbefugte Weitergabe dieser E-Mail ist nicht gestattet.

This e-mail may contain confidential information.
If you are not the intended recipient (or have received this e-mail in error)
please notify the sender immediately and destroy this e-mail.
Any unauthorised copying, disclosure or distribution of the material in this e-mail is strictly forbidden.

Re: driver or calculation of load average wrong ?

[Alexander Clouter]

Frank Salomon <frank.salomon@wincor-nixdorf.com> wrote:
> 
> I have the following configuration:
> - CentOS 5
> - kernel 2.6.20.1
> - My own driver in a kernel_thread:
>
> [snipped NDA'd information]
> 
> Any help or comments would be really great?
> 
> Best regards, thanks, Frank
> -- 
> WINCOR NIXDORF International GmbH
> Retail Store Solutions
> Heinz-Nixdorf-Ring 1
> 33106 Paderborn
> Tel. +49 (0) 30 5017 1335
> Fax +49 (0) 30 5017 1305
> mail frank.salomon@wincor-nixdorf.com
> 
> WINCOR NIXDORF International GmbH
> Sitz der Gesellschaft: Paderborn
> Registergericht Paderborn HRB 3507
> Geschäftsführer: Eckard Heidloff (Vorsitzender), Stefan Auerbach, Dr. Jürgen Wunram
> Vorsitzender des Aufsichtsrats: Karl-Heinz Stiller
> Steuernummer: 339/5884/0020 - Ust-ID Nr.: DE812927716 - WEEE-Reg.-Nr. DE44477193
> 
> Diese E-Mail enthält vertrauliche Informationen.
> Wenn Sie nicht der richtige Adressat sind oder diese E-Mail irrtümlich erhalten haben,
> informieren Sie bitte sofort den Absender und vernichten Sie diese E-Mail.
> Das unerlaubte Kopieren sowie die unbefugte Weitergabe dieser E-Mail ist nicht gestattet.
> 
> This e-mail may contain confidential information.
> If you are not the intended recipient (or have received this e-mail in error)
> please notify the sender immediately and destroy this e-mail.
> Any unauthorised copying, disclosure or distribution of the material in this e-mail is strictly forbidden.
>
...alas I have to consult with my lawyer before being able to help.

Cheers

-- 
Alexander Clouter
.sigmonster says: BOFH excuse #153:
                  Big to little endian conversion error

Re: driver or calculation of load average wrong ?

[Greg KH]

On Mon, Oct 11, 2010 at 08:24:49AM +0200, Frank Salomon wrote:
> Hello All,
>
> I have the following configuration:
> - CentOS 5
> - kernel 2.6.20.1
> - My own driver in a kernel_thread:
> 		while ( 1 ){
> 			printk ( KERN_INFO "go sleep, %lu\n", jiffies );
> 			current -> state = TASK_UNINTERRUPTIBLE;
> 			schedule_timeout ( msecs_to_jiffies(4000) );

Change this to schedule_timeout_interruptable() and your load average
calculation will go back to what you expect it to.

hope this helps,

greg k-h