Hi Robin,
You can more then double your performance with DateTime::Format::Strptime by
instantiating a parser object and reusing it. You should also keep in mind
that Time::Piece doesn't really support leapseconds (it may be able to parse
them on some platforms if it's using gmtime(3)... haven't looked at the
source).
--
use Time::Piece;
use Benchmark qw( cmpthese );
use DateTime::Format::Strptime qw( strptime );
my $dtstrp = DateTime::Format::Strptime->new( pattern => "%Y-%m-%dT%H%M%S");
cmpthese ( -3,
{
'DT Strptime' => sub {
$dtstrp->parse_datetime("2004-10-10T101010");
},
'DT Strptime imported' => sub {
strptime("%Y-%m-%dT%H%M%S", "2004-10-10T101010");
},
'Time::Piece' => sub {
Time::Piece->strptime("2004-10-10T101010", "%Y-%m-%dT%H%M%S");
},
}
);
--
Rate DT Strptime imported DT Strptime Time::Piece
DT Strptime imported 1338/s -- -54% -98%
DT Strptime 2916/s 118% -- -97%
Time::Piece 85687/s 6305% 2839% --
Cheers,
-J
--
On Thu, 9 Sep 2004, Robin Phillips wrote:
> Hi,
>
> I have been converting a couple of programs that were using Time::Piece as
> their date/time handling module, to use DateTime.pm instead.
>
> However it seems that DateTime.pm apears to be about 700 times slower
> than Time::Piece when parsing dates.
>
> The little program below takes 15 seconds to do 10,000 calls to the new
> strptime and only 2 seconds to do 100,000 (ie 10x more) calls to the old
> version (on my machine).
>
> Is this something to do with Time::Piece using a C library and DateTime
> doing things in perl instead? Or is there some otherway of doing this date
> parsing using DateTime that is faster?
>
> Robin
>
> -------------------------------------------------
> #!/usr/bin/perl -w
> use strict;
> use DateTime ;
> use DateTime::Format::Strptime qw{strptime};
> use Time::Piece;
>
> print gmtime->datetime, "\n";
> for (my $i =0; $i <=10_000; $i++) {
> my $file_datetime = strptime("%Y-%m-%dT%H%M%S", "2004-10-10T101010");
> }
>
> print gmtime->datetime, "\n";
>
> for (my $i =0; $i <=100_000; $i++) {
> my $file_datetime = Time::Piece -> strptime("2004-10-10T101010",
> "%Y-%m-%dT%H%M%S");
> }
>
> print gmtime->datetime, "\n";
>
> exit;
>
>
>
>
>
