You right about RSS/VSZ: 
### x86
# perl -le 'use version; print $version::VERSION; system "ps -p $$ -o 
+rss,vsz,comm"'
0.96
  RSS    VSZ COMMAND
 2068   5552 perl
### x86_64
# perl -le 'use version; print $version::VERSION; system "ps -p $$ -o 
+rss,vsz,comm"'
0.96
  RSS    VSZ COMMAND
 2468  20044 perl

[download]
But thing is, virtual or resident, memory limits should be significantly increased on 64-bit systems. Real issue I had because of this was related to qmail (which by default run under setlimit) filter - perl script which implement greylisting.

As you see, when perl doesn't get enough memory it's error messages ain't very informative. So, that I got in system logs is useless messages about my locale, coming from unknown source - and at that time my system rejects incoming emails because part of qmail execution chain was crashed.

And it's still doesn't clear for me, is so much virtual memory requested by perl on 64-bit system is a bug in perl, or correct behaviour.

In reply to Re^2: memory usage on x86_64 by powerman
in thread memory usage on x86_64 by powerman

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