* Ken Chen <[EMAIL PROTECTED]> wrote:

> schedstat is useful in investigating CPU scheduler behavior.  Ideally, 
> I think it is beneficial to have it on all the time.  However, the 
> cost of turning it on in production system is quite high, largely due 
> to number of events it collects and also due to its large memory 
> footprint.
> 
> Most of the fields probably don't need to be full 64-bit on 64-bit 
> arch.  Rolling over 4 billion events will most like take a long time 
> and user space tool can be made to accommodate that.  I'm proposing 
> kernel to cut back most of variable width on 64-bit system.  (note, 
> the following patch doesn't affect 32-bit system).

thanks, applied.

note that current -git has a whole bunch of new schedstats fields in 
/proc/<PID>/sched which can be used to track the exact balancing 
behavior of tasks. It can be cleared via echoing 0 to the file - so 
overflow is not an issue. Most of those new fields should probably be 
unsigned int too. (they are u64 right now.)

        Ingo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to