Re: [Patch] task interactivity calculation (was Strange interactivitybehaviour)

From: Martin Andersson
Date: Tue Feb 28 2006 - 10:03:28 EST


>On Tue, 2006-02-28 at 11:33 +0100, Martin Andersson wrote:
The appended patch fixes the problem mentioned in http://lkml.org/lkml/2006/2/27/104
regarding wrong truncations in the calculation of task interactivity when the nice value is negative. The problem causes the interactivity to scale nonlinearly and differ from examples in the code.

Hi Mike,

Point taken. Is it correct now?

/Martin

Signed-off-by: Martin Andersson <martin.andersson@xxxxxxxxxxxxxx>

diff -uprN linux-2.6.15.4.orig/kernel/sched.c linux-2.6.15.4/kernel/sched.c
--- linux-2.6.15.4.orig/kernel/sched.c 2006-02-10 08:22:48.000000000 +0100
+++ linux-2.6.15.4/kernel/sched.c 2006-02-28 15:49:12.000000000 +0100
@@ -142,7 +142,8 @@
(v1) * (v2_max) / (v1_max)

#define DELTA(p) \
- (SCALE(TASK_NICE(p), 40, MAX_BONUS) + INTERACTIVE_DELTA)
+ (SCALE(TASK_NICE(p) + 20, 40, MAX_BONUS) - 20 * MAX_BONUS / 40 + \
+ INTERACTIVE_DELTA)

#define TASK_INTERACTIVE(p) \
((p)->prio <= (p)->static_prio - DELTA(p))
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/