Commit 68158234 authored Jun 22, 2011 by Christian Borntraeger Committed by Martin Schwidefsky Jun 22, 2011

[S390] hwsampler: Set a sane default sampling rate



The sampling interval for the hardware sampler is specified in cycles.
(see SA23-2260-01 The Load-Program-Parameter and the CPU-Measurement
Facilities)
The current default value will therefore result in millions of samples.
This patch changes the default sampling interval to 4M, which will
result in ~1500 samples per second on a z196 reducing the overhead
of sampling.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

parent b530ce7a

arch/s390/oprofile/init.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -25,7 +25,7 @@ extern void s390_backtrace(struct pt_regs * const regs, unsigned int depth);

		#include "hwsampler.h"

		#define DEFAULT_INTERVAL 4096
		#define DEFAULT_INTERVAL 4127518

		#define DEFAULT_SDBT_BLOCKS 1
		#define DEFAULT_SDB_BLOCKS 511