Re: [9fans] Re: patch/list sorry/proc-mtime

[uriel@cat-v.org]

There is also /n/sources/contrib/uriel/scripts/atop, a graphical top
in C by 20h and a version by f2f in perl, the existence of the perl
version pissed me off so much that I had to rewrite it in awk and IIRC
halve the line count in the process.  We all love to duplicate work.

Anyway, it is usually a good idea to dig around the [contrib index] wiki
page, often one finds useful things. I'm still wondering why g " and "' are
not part of the standard distribution.

uriel

> i was about to say that i'd find it useful if the atime of /proc/n
> reflected the last run time of a process, to make it easier to find
> cpu hogs, but russ's point about ls -lt /proc's uselessness is bang
> on.
>
> so, by way of a little script to help with the above problem, which
> bugs me every so often, here's "hogs", a poor man's replacement for
> unix's "top" - it's like ps except that it sorts the processes by the
> amount of time they've used over the last t (default 1) seconds.
>
> it displays percentage of time used over the sample time (this might
> be >100% with multiple cpus), and combines user, syscall and child
> time into the second time column (to make it easier to find processes
> that spawn lots of transient cpu-eating processes but don't do much
> themselves); otherwise the output format is the same as for ps(1).
>
> YMMV - i imagine others have similar scripts.
>
> cat >$home/bin/rc/hogs <<'EOF'
> #!/bin/rc
> # usage: hogs [sampletime]
> t=1
> if(! ~ $#* 0){
> 	t = $1
> }
> {
> 	cd /proc
> 	for(i in [0-9]*){
> 		cat $i/status && echo $i
> 	}
> 	echo
> 	sleep $t
> 	for(i in [0-9]*){
> 		cat $i/status && echo $i
> 	}
> } | awk '
> 	phase == 0 && /./ {
> 		t0[$13] = $4+$5+$7+$8;
> 		rt0[$13] = $6
> 		next
> 	}
> 	phase == 0 && /^$/ {
> 		phase = 1;
> 		next
> 	}
> 	phase != 0 {
> 		t1[$13] = $4+$5+$7+$8
> 		rt1[$13] = $6
> 		line[$13] = $0
> 	}
> 	END {
> 		for(i in line){
> 			n = split(line[i], p, " ");
> 			dt = ((t1[i] - t0[i] + 0.0) / (rt1[i] - rt0[i])) * 100
> 			utime = (p[4]+p[4]+p[7]+p[8]) / 1000;
> 			size = p[9];
> 			if(dt >= 1 || utime >= 1){
> 				printf("%-10s %8s %3d%% %4d.%.2d %7dK %-8.8s %s\n",
> 					p[2],
> 					i,
> 					dt,
> 					utime/60, utime%60,
> 					size,
> 					p[3],
> 					p[1]);
> 			}
> 		}
> 	}' |
> 	sort +2rn -3rn +3rn |
> 	sed 's/(^[^ ]+ +[0-9]+ +[0-9]+% +[0-9]+)\./\1:/'
> EOF