.\"	$NetBSD: kvm_getloadavg.3,v 1.13 2018/12/11 23:02:19 sevan Exp $
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.\"     @(#)kvm_getloadavg.3	8.1 (Berkeley) 6/4/93
.\"
.Dd December 11, 2018
.Dt KVM_GETLOADAVG 3
.Os
.Sh NAME
.Nm kvm_getloadavg
.Nd get system load averages, from live or dead kernels
.Sh LIBRARY
.Lb libkvm
.Sh SYNOPSIS
.In sys/resource.h
.In kvm.h
.Ft int
.Fn kvm_getloadavg "kvm_t *kd" "double loadavg[]" "int nelem"
.Sh DESCRIPTION
The
.Fn kvm_getloadavg
function returns the number of processes in the system run queue
of the kernel or core file, indicated by
.Fa kd .
Up to
.Fa nelem
samples are retrieved and assigned to successive elements of
.Fa loadavg Ns Bq .
The system imposes a maximum of 3 samples, representing averages
over the last 1, 5, and 15 minutes, respectively.
On a live system, the load average is obtained by calling
.Xr getloadavg 3 .
If performing post mortem on a kernel core file,
.Nm
is able to extract the system load averages at the time of death from the core
file directly.
.Sh RETURN VALUES
If the load average was unobtainable, \-1 is returned; otherwise,
the number of samples actually retrieved is returned.
.Sh SEE ALSO
.Xr uptime 1 ,
.Xr getloadavg 3 ,
.Xr kvm 3 ,
.Xr kvm_open 3 ,
.Xr sysctl 3