From 0c2043abefacac97b6d01129c1123a466c95b7c1 Mon Sep 17 00:00:00 2001 From: Linus Torvalds <torvalds@woody.linux-foundation.org> Date: Sun, 7 Oct 2007 16:17:38 -0700 Subject: [PATCH] Don't do load-average calculations at even 5-second intervals MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It turns out that there are a few other five-second timers in the kernel, and if the timers get in sync, the load-average can get artificially inflated by events that just happen to coincide. So just offset the load average calculation it by a timer tick. Noticed by Anders Boström, for whom the coincidence started triggering on one of his machines with the JBD jiffies rounding code (JBD is one of the subsystems that also end up using a 5-second timer by default). Tested-by: Anders Boström <anders@bostrom.dyndns.org> Cc: Chuck Ebbert <cebbert@redhat.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- include/linux/sched.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index a01ac6dd5f5e1..313c6b6e774f8 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -113,7 +113,7 @@ extern unsigned long avenrun[]; /* Load averages */ #define FSHIFT 11 /* nr of bits of precision */ #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ -#define LOAD_FREQ (5*HZ) /* 5 sec intervals */ +#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ #define EXP_5 2014 /* 1/exp(5sec/5min) */ #define EXP_15 2037 /* 1/exp(5sec/15min) */ -- GitLab