diff options
| -rw-r--r-- | sys/kern/kern_synch.c | 9 | ||||
| -rw-r--r-- | sys/kern/tty_info.c | 2 | ||||
| -rw-r--r-- | sys/sys/param.h | 8 |
3 files changed, 10 insertions, 9 deletions
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c index e78878987b57..381d6315044c 100644 --- a/sys/kern/kern_synch.c +++ b/sys/kern/kern_synch.c @@ -87,7 +87,7 @@ struct loadavg averunnable = * Constants for averages over 1, 5, and 15 minutes * when sampling at 5 second intervals. */ -static fixpt_t cexp[3] = { +static uint64_t cexp[3] = { 0.9200444146293232 * FSCALE, /* exp(-1/12) */ 0.9834714538216174 * FSCALE, /* exp(-1/60) */ 0.9944598480048967 * FSCALE, /* exp(-1/180) */ @@ -611,14 +611,15 @@ setrunnable(struct thread *td, int srqflags) static void loadav(void *arg) { - int i, nrun; + int i; + uint64_t nrun; struct loadavg *avg; - nrun = sched_load(); + nrun = (uint64_t)sched_load(); avg = &averunnable; for (i = 0; i < 3; i++) - avg->ldavg[i] = (cexp[i] * avg->ldavg[i] + + avg->ldavg[i] = (cexp[i] * (uint64_t)avg->ldavg[i] + nrun * FSCALE * (FSCALE - cexp[i])) >> FSHIFT; /* diff --git a/sys/kern/tty_info.c b/sys/kern/tty_info.c index 60675557e4ed..237aa47a18da 100644 --- a/sys/kern/tty_info.c +++ b/sys/kern/tty_info.c @@ -302,7 +302,7 @@ tty_info(struct tty *tp) sbuf_set_drain(&sb, sbuf_tty_drain, tp); /* Print load average. */ - load = (averunnable.ldavg[0] * 100 + FSCALE / 2) >> FSHIFT; + load = ((int64_t)averunnable.ldavg[0] * 100 + FSCALE / 2) >> FSHIFT; sbuf_printf(&sb, "%sload: %d.%02d ", tp->t_column == 0 ? "" : "\n", load / 100, load % 100); diff --git a/sys/sys/param.h b/sys/sys/param.h index 2d463b9ac7a2..b0b53f1a7776 100644 --- a/sys/sys/param.h +++ b/sys/sys/param.h @@ -361,12 +361,12 @@ __END_DECLS * Scale factor for scaled integers used to count %cpu time and load avgs. * * The number of CPU `tick's that map to a unique `%age' can be expressed - * by the formula (1 / (2 ^ (FSHIFT - 11))). The maximum load average that - * can be calculated (assuming 32 bits) can be closely approximated using - * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15). + * by the formula (1 / (2 ^ (FSHIFT - 11))). Since the intermediate + * calculation is done with 64-bit precision, the maximum load average that can + * be calculated is approximately 2^32 / FSCALE. * * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age', - * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024. + * FSHIFT must be at least 11. This gives a maximum load avg of 2 million. */ #define FSHIFT 11 /* bits to right of fixed binary point */ #define FSCALE (1<<FSHIFT) |