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scheduler help

DISCUSSION alexis 5 participants 5 messages Dec 8, 2014

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alexis

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#0 lore raw

hello to everyone ,
l have a assignment and i need help.
i have to change the scheduler function at kernel 2.6.38 so that the scheduler choose the process
with the least slack time.

My problem :
i have create a function that iterates all runnable processes finds the one with least slack time(lst)
and returns a pointer to the task( struct task_struct*)
Now i need to change the scheduler so that selected for execution the process with lst.

i am trying to change the function pick_next_task_fair in file sched_fair.c but i cant understand the code in there can someone explain me ?

is the pick_next_task_fair the right function that need change? if yes it is the only one ?

sorry for my English
thanks.

#1 lore raw

Your English is fine.

Use a modern kernel, nobody wants to support development of 2.6.x. It's nearly four years old.

sched_fair.c was moved to kernel/sched/fair.c in 2011, prior to release of version 3.3. It has had 345 changes since then.

I realize this is for a class; you should tell your instructor that they should update the course to use a modern kernel version. If enough people do that, maybe it will eventually happen.

Good luck,
Henry

Quoted 27 lines · alexis

hello to everyone ,
l have a assignment and i need help.
i have to change the scheduler function at kernel 2.6.38 so that the scheduler choose the process
with the least slack time.

My problem :
i have create a function that iterates all runnable processes finds the one with least slack time(lst)
and returns a pointer to the task( struct task_struct*)
Now i need to change the scheduler so that selected for execution the process with lst.

i am trying to change the function pick_next_task_fair in file sched_fair.c but i cant understand the code in there can someone explain me ?

is the pick_next_task_fair the right function that need change? if yes it is the only one ?

sorry for my English
thanks.

_______________________________________________
Kernelnewbies mailing list
Kernelnewbies at kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

#2 lore raw
Quoted 2 lines · you

Use a modern kernel, nobody wants to support development of 2.6.x. It's nearly four years old.

More correctly, nobody wants to support 2.6.x *for free*. There's plenty of people who work for distros who will support 2.6.x if you pay them in the form of buying a support contract....

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#3 lore raw
In reply to alexis

I am sure you can get help in Linux mailing list as kernel newbies list would not be be able to answer this.I think there is specific scheduler mailing list.

Quoted 29 lines · alexis

hello to everyone ,
l have a assignment and i need help.
i have to change the scheduler function at kernel 2.6.38 so that the scheduler choose the process
with the least slack time.

My problem :
i have create a function that iterates all runnable processes finds the one with least slack time(lst)
and returns a pointer to the task( struct task_struct*)
Now i need to change the scheduler so that selected for execution the process with lst.

i am trying to change the function pick_next_task_fair in file sched_fair.c but i cant understand the code in there can someone explain me ?

is the pick_next_task_fair the right function that need change? if yes it is the only one ?

sorry for my English
thanks.

_______________________________________________
Kernelnewbies mailing list
Kernelnewbies at kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

#4 lore raw
Quoted 3 lines · Anish Kumar

I am sure you can get help in Linux mailing list as kernel newbies list would not be be able to answer this.I think there is specific scheduler mailing list.

People do not answer other people's homework questions on public mailing lists. Or they do so in ways that guarantee they will get a bad grade, so beware...