This is difficult to formulate. But I have a nice machine besides my (ultra powerful) PIII-256MB I have a p133-64Mb
I'm trying to save memory on this machine and in my hunt I stumbled on a memory hog. My logcoloriser(1.9Mb), I run two of them.

In my inittab I have for tty8 and tty9:
tail -f /var/log/messages | /usr/local/bin/logcolorise
On tty9 I have a network log with logcolorise to ...

So my question is : is there a way(or reading material about it) how I can re-program this program to be less memory-consuming.

I'm looking for general tips so I can do this in the future by myself.


Here is the logcolorise program(it's not my own!!!!):

#!/usr/bin/perl
# logcolorize.pl 1.0.8 - A PERL script to colorize log viewing
#
# Copyright: (C) 1999, Michael T. Babcock
#                      <mikebabcock@pobox.com>
#                      http://www.linuxsupportline.com/~pgp/linux/
#
#   This program is free software; you can redistribute it and/or modi
+fy
#   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.
#
#   For revisional changes, see ChangeLog file
#
######################################################################
$black    = "\033[30m";
$red      = "\033[31m";
$green    = "\033[32m";
$yellow   = "\033[33m";
$blue     = "\033[34m";
$magenta  = "\033[35m";
$purple   = "\033[35m";
$cyan     = "\033[36m";
$white    = "\033[37m";
$darkgray = "\033[30m";

# Define global terms:
# Define good notables:
@word_good=("starting\n", "Freeing", "Detected", "starting.", "accepte
+d.\n", "authenticated.\n", "Ready", "active", "reloading", "saved;", 
+"restarting", "ONLINE\n");
@word_warn=("dangling", "closed.\n", "Assuming", "root", "root\n", "ex
+iting\n", "missing", "Ignored", "adminalert:", "deleting", "OFFLINE\n
+");
@word_bad=("bad");
@word_note=("LOGIN", "DHCP_OFFER", "optimized", "reset:", "unloaded", 
+"disconnected", "connect", "Successful", "registered\n");
@line_good=("up", "DHCP_ACK", "Cleaned", "Initializing", "Starting", "
+success", "successfully", "alive", "found", "ONLINE\n");
@line_warn=("warning:", "WARNING:", "invalid", "obsolete", "bad", "Pas
+sword", "detected", "timeout", "timeout:", "attackalert:", "wrong", "
+Lame", "FAILED", "failing", "unknown", "obsolete", "stopped.\n", "ter
+minating.", "disabled\n", "disabled", "Lost");
@line_bad=("DENY", "lost", "shutting", "dead", "DHCP_NAK", "failure;",
+ "Unable", "inactive", "terminating", "refused", "rejected", "down", 
+"OFFLINE\n", "error\n", "ERROR\n", "ERROR:", "error", "ERROR", "error
+:", "failed:");

# Define specifics:
@daemons=("named");

# Now define what we want to use when:
$col_good = $green;
$col_warn = $yellow;
$col_bad = $red;
$col_note = $purple;

$col_norm =        "\033[00m";
$col_background =    "\033[07m";
$col_brighten =     "\033[01m";
$col_underline =     "\033[04m";
$col_blink =         "\033[05m";

# Resets to normal colours and moves to the left one column ... 
$col_default = "$col_norm$white";
print "\n$col_norm$cyan";
print "logcolorize.pl 1.0.8 by$col_brighten$cyan Michael T. Babcock$co
+l_norm$cyan <$col_brighten$green";
print "mikebabcock\@pobox.com$col_norm$cyan";
print ">\n";

$datespace=0;

mainloop: while (<>)
{
    $thisline = $_;

    $timestamp = substr($_,0,15);
    s/................//;

    @rec = split (/ /, $_);

    $output="$col_brighten$cyan$timestamp";    # date & time
    $output.=" $col_brighten$blue$rec[0]";    # hostname
    if ($rec[1] eq "last")
    {
        $output.="$col_norm$green last message repeated ";
        $output.="$col_brighten$rec[4]$col_norm$green times\n";
        print "$output$col_default";
        next mainloop;
    }
    # Extract PID if present
    if ($rec[1] =~ /\[(\d+)\]\:/)
    {
        my($pid) = $1;
        $rec[1]=~s/\[$1\]\:// ;
        $output .= "$col_norm$green $rec[1]" .
                   "$col_brighten$green\[";
        $output .= "$col_brighten$white$pid" .
                   "$col_brighten$green\]: ";
    }
    else {
        $output .= "$col_norm$green $rec[1] ";
    }

    $restcolor="$col_norm$cyan";
    $restoftheline="";
    for ($therest=(2); $therest<=$#rec; $therest++)
    {    $highlight=0;

        # Check for keywords to highlight

        for ($i=0; $i<=$#word_good; $i++)
        {    if ($word_good[$i] eq $rec[$therest])
            { $restoftheline.="$col_brighten$col_good"; $highlight=1; 
+}
        }
        for ($i=0; $i<=$#word_warn; $i++)
        {    if ($word_warn[$i] eq $rec[$therest])
            { $restoftheline.="$col_brighten$col_warn"; $highlight=1; 
+} 
        }
        for ($i=0; $i<=$#word_bad; $i++)
        {    if ($word_bad[$i] eq $rec[$therest])
            { $restoftheline.="$col_brighten$col_bad"; $highlight=1; }
+ 
        }
        for ($i=0; $i<=$#word_note; $i++) 
        {    if ($word_note[$i] eq $rec[$therest])
            { $restoftheline.="$col_brighten$col_note"; $highlight=1; 
+} 
        }

        # Watch for words that indicate entire lines should be highlig
+hted

        for ($i=0; $i<=$#line_good; $i++)
        {    if ($line_good[$i] eq $rec[$therest])
            { $restcolor="$col_norm$col_good";
              $restoftheline.="$col_brighten$col_good"; $highlight=1; 
+}
        }
        for ($i=0; $i<=$#line_warn; $i++)
        {    if ($line_warn[$i] eq $rec[$therest])
            { $restcolor="$col_norm$col_warn";
              $restoftheline.="$col_brighten$col_warn"; $highlight=1; 
+}
        }
        for ($i=0; $i<=$#line_bad; $i++)
        {    if ($line_bad[$i] eq $rec[$therest])
            { $restcolor="$col_norm$col_bad";
              $restoftheline.="$col_brighten$col_bad"; $highlight=1; }
        }

        $restoftheline.="$rec[$therest] ";
        if ($highlight == 1)
        { $restoftheline.=$restcolor; }
    }
    $output.="$restcolor$restoftheline";
    print "$output$col_default\033[1G";
}

exit(0);
[download]

I know how to benchmark for speed, but this time I want tot reduce memory. Maybe somebody can write a nice tutorial about it.
I feel in these days where ram is cheap nobody cares anymore about writing programs that doesn't eat all your memory... or am I wrong ????
My opinions may have changed,
but not the fact that I am right