Article 5393 of comp.lang.perl:
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From:
[email protected] (Tim Bunce)
Path: feenix.metronet.com!news.ecn.bgu.edu!psuvax1!uwm.edu!math.ohio-state.edu!cs.utexas.edu!uunet!news!demon!ig.co.uk!timbo
Subject: Re: What's the difference?
References: <
[email protected]> <
[email protected]> <
[email protected]> <
[email protected]>
Organisation: Paul Ingram Group, Software Systems, +44 483 424424
Date: Thu, 26 Aug 1993 18:13:25 +0000
Message-ID: <
[email protected]>
Sender:
[email protected]
Lines: 74
From the keyboard of
[email protected] (Tom Christiansen):
>From the keyboard of
[email protected] (Tim Bunce):
>:join: 52 cpu seconds
>:interp: 60 cpu seconds
>:concat: 95 cpu seconds
>:sprintf: 75 cpu seconds
>
>Try it on Perl5.
>
>--tom
> Tom Christiansen
[email protected] 303-444-3212
Ok, here it is...
Roy Johnson <
[email protected]> kindly pointed out that I wasn't quite fair
(in my original post) to interpolation and sprintf, as I made them print commas
when join and concat didn't have to.
So I've modified the tests slightly and rerun them for perl4 and perl5:
Interp: $x = "$a::$b::$c::$d::$e\n"
Join: $x = join('',$a,'::',$b,'::',$c,'::',$d,'::',$e,"\n")
Concat: $x = $a.'::'.$b.'::'.$c.'::'.$d.'::'.$e."\n"
Sprintf: $x = sprintf("%s::%s::%s::%s::%s\n", $a,$b,$c,$d,$e);
Results: Perl4 Perl5a2
Interp: 54.52 => 72.38 cpu seconds
Join: 60.27 => 67.32 cpu seconds
Concat: 136.88 => 73.18 cpu seconds
Sprintf: 68.58 => 77.60 cpu seconds
Note that the Perl4 is a fully optimised binary whereas the Perl5 is the
stock out-of-the-box sparc binary built by Larry with no optimisation at all.
If anyone has rebuilt perl5 with optimisation I'd be VERY interested in their
own perl4 vs perl5 figures.
For the curious, here's the code I used:
#!/usr/local/bin/perl
($a,$b,$c,$d,$e) = ('1234567890') x 5;
$loop = 1000000;
print "\n";
&trial("Interp", <<'END');
$x="$a::$b::$c::$d::$e\n"
END
&trial("Join", <<'END');
$x=join('',$a,'::',$b,'::',$c,'::',$d,'::',$e,"\n")
END
&trial("Concat", <<'END');
$x=$a.'::'.$b.'::'.$c.'::'.$d.'::'.$e."\n"
END
&trial("Sprintf", <<'END');
$x=sprintf("%s::%s::%s::%s::%s\n", $a,$b,$c,$d,$e);
END
sub trial{
local($title, $code) = @_;
eval join('','($u1,$s1)=times; $i=0;',
'while($i++ < $loop){', $code, '};',
'($u2,$s2)=times');
printf("$title: %.2f cpu seconds $@\n\n", ($u2+$s2)-($u1+$s1));
}
Regards,
Tim Bunce.
