#!/usr/local/bin/perl

# na_top - display current top NFS clients for a NetApp
# Copyright (C) 1998  Daniel Quinlan
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

$default_interval = 60;
$prog = $0;
$prog =~ s@.*/@@;

require "getopts.pl";
&Getopts("hi:");

if (defined $ENV{"LINES"} && $ENV{"LINES"} ne "") {
    $lines = $ENV{"LINES"};
}
else {
    $lines = 24;
}

if ($opt_h) {
    &usage;
    exit 0;
}
if ($opt_i && $opt_i > 0) {
    $interval = $opt_i;
}
else {
    $interval = $default_interval;
}

if ($ARGV[0]) {
    $host = $ARGV[0];
}
else {
    &usage;
    exit 1;
}

sub usage {
    print <<EOF;
usage: $prog [options] filer
 -h            print this help
 -i n          report filer statistics every n seconds ($default_interval is default)

 The NetApp must have the "nfs.per_client_stats.enable" option
 "on" for this to work at all.

 This program must be run this from an admin host as root.
EOF
}

sub print_top {
    my $total = 0;
    my $diff;
    my %recent;

    foreach $key (keys %nfs_ops_last) {
	$diff = $nfs_ops{$key} - $nfs_ops_last{$key};
	$recent{$key} = $diff;
	$total += $diff;
    }
    $total = int ($total / $interval);
    system("clear");
    printf "%6s\t%s\n", "NFS/s",
	"total NFS/s = $total | interval = $interval";
    printf "%6s\t%s\n", "------", "----------------------------------------";
    $i = 0;
    foreach $key (sort {$recent{$b} <=> $recent{$a} } keys %recent) {
	printf "%6d\t%s\n", int ($recent{$key} / $interval + 0.5),
	    $ip_name{$key};
	last if ($i++ > ($lines - 5));
    }
}

$first = 1;
for (;;) {
    $time_0 = time();
    open(NFSSTAT, "rsh $host nfsstat -l|");
    while (<NFSSTAT>) {
	@tmp = split;

	# ip_address = tmp[0]
	# ip_name    = tmp[1]
	# nfs_ops    = tmp[4]
	
	$ip_name{$tmp[0]} = $tmp[1];
	$nfs_ops{$tmp[0]} = $tmp[4];
    }
    close(NFSSTAT);
    if (! $first) {
	&print_top;
    }
    else {
	$first = 0;
    }
    %nfs_ops_last = %nfs_ops;
    $time_1 = time();
    sleep ($interval - ($time_1 - $time_0));
}