Finding load average on Iris 4D

[Rayan Zachariassen]

In article <33027 at bu-cs.BU.EDU> eap at bu-it.bu.edu (Eric A. Pearce) writes:
#   Is there a way to get a load average on the Iris?   The BSD way
#   would be to nlist the kernel and find "_avenrun", but I did not see
#   anything similar on the Iris.   

There are a couple of system calls that return all kinds of poorly
documented kernel stats.  Unfortunately I don't see anything that
returns the load average directly.  Here is the closest I've come
while fiddling around with this (I wish this was in the kernel...):


#include <stdio.h>
#include <sys/types.h>
#include <sys/sysmp.h>
#include <sys/sysinfo.h>

#define	INTERVAL	5

#define	NSAMPLES (15 /* minutes */ * 60 /* sec/min */ / INTERVAL)

int ringload[NSAMPLES];
int ringindex = 0;

main()
{
	struct sysinfo sinfo;
	int flag = 0, now, last1, last5, last15;

	setvbuf(stdout, (char *)NULL, _IOLBF, 0);
	for (;;) {
		now = ringindex;
		sysmp(MP_SAGET, MPSA_SINFO, &sinfo, sizeof sinfo);
		ringload[ringindex++] = sinfo.runque;
		if (!flag) {
			while (flag < NSAMPLES)
				ringload[flag++] = sinfo.runque;
			if (!flag)
				break;	/* shut up the compiler */
		}
		ringindex %= NSAMPLES;
		last1 = (NSAMPLES + now - 60 / INTERVAL)%NSAMPLES;
		last5 = (NSAMPLES + now - 5*60 / INTERVAL)%NSAMPLES;
		last15 = ringindex;
		printf("%6.2f %6.2f %6.2f\n",
		    (ringload[now] - ringload[last1])/60.0,
		    (ringload[now] - ringload[last5])/(5*60.0),
		    (ringload[now] - ringload[last15])/(15*60.0));
		sleep(INTERVAL);
	}
	/* NOTREACHED */
	exit(0);
}