Working with a smaller, bounded subset might help:
# reduce the working set size by intersecting with a smaller span
$total_span_set = $total_span_set-intersection(
DateTime::Span-new(
start = DateTime-new( year = 2003, month = 1, day = 1 ),
before = DateTime-new( year = 2003, month = 3, day = 1 )
)
);
Also changing the set time zone inside a loop can be expensive.
It would be better to move the call to $dt_set-set_time_zone() to
outside of the loops.
Flávio S. Glock
2010/12/1 Per-Olof Jensen per.jen...@bolderthinking.com:
I've been running into the issue of having a SpanSet being incredibly slow
when doing a -contains on a DateTime-now object. I've tried spreading the
spanset into an array of spans. That becomes much faster, but only if there
is no time zone set on those spans. The moment I put time zones on those
'not unioned' spans I get a massive slowdown in computation time. This is
going into a large scale project, and I was hoping that this feature would
be able to be used since it does exactly what I need it to do!
Our goal is to take a group of spans and check if the time right now is
within each span (basically a daily schedule across the globe).
Here's a test program illustrating the problem I'm having. I'm just
wondering if there is any way to make the -contains faster.
#!/usr/bin/perl
use DateTime::Event::Recurrence;
use DateTime::SpanSet;
use DateTime::Infinite;
use DateTime::Set;
use DateTime;
my ($total_span_set, $start, $end, $spanset);
my @array;
my %tzhash = (
'1' = 'America/Halifax',
'2' = 'America/New_York',
'3' = 'America/Chicago',
'4' = 'America/Denver',
'5' = 'America/Los_Angeles',
'6' = 'America/Nome',
'7' = 'Pacific/Honolulu',
'8' = 'Asia/Tokyo',
);
$x = 7;
while ($x 0 ){
# Make the set representing the work start times: M-F 9:00 and 13:00
$start = DateTime::Event::Recurrence-weekly
( days = $x%6+1, hours = 00 , minutes = 00);
# Make the set representing the work end times: M-F 12:00 and 17:00
$end = DateTime::Event::Recurrence-weekly
( days = $x%6+1, hours = 23, minutes = 59);
# Build a spanset from the set of starting points and ending points
$spanset = DateTime::SpanSet-from_sets
( start_set = $start,
end_set = $end );
if ($total_span_set){$total_span_set = $total_span_set-union($spanset)}
else {$total_span_set = $spanset}
push(@array, $spanset);
$x--;
}
# Iterate from Thursday the 3rd to Monday the 6th
my $it = $spanset-iterator
(start =
DateTime-new(year = 2003, month = 1, day = 3),
before =
DateTime-new(year = 2003, month = 1, day = 7));
while (my $span = $it-next) {
my ($st, $end) = ($span-start(), $span-end());
print $st-day_abbr, , $st-hour, to , $end-hour, \n;
}
my $dt = DateTime-new(year = 2003, month = 2, day = 11, hour = 11);
my $timer = DateTime-now;
#Here I'm using the first way. Using a spanet seems very slow on 'contains'
regardless of having a timezone set or not for the span
my $x = 3;
while( $x ){
$dt-set_time_zone($tzhash{$x%6 + 1});
#Setting a time zone to the SpanSet doesn't seem to affect search time
$total_span_set-set_time_zone($tzhash{2});
if ($total_span_set-contains( $dt )){
print Found time! \n;
}
}
$result = $timer - DateTime-now;
print Total time : .$result-seconds.\n;
#An array of spans, this seems to be very fast without timezones set
$timer = DateTime-now;
$x = 3;
while( $x ){
foreach(@array){
#Setting a time zone to the SpanSet/Spans really hoses search time
$_-set_time_zone($tzhash{2});
if ($_-contains( $dt )){
print Found time\n;
}
}
$x--;
}
$result = $timer - DateTime-now;
print Total time : .$result-seconds.\n;
--
Per Jensen
Bolder Thinking - Software Developer
