Net::P...togram(3pm)

💖 NAME 💖

Net::Prometheus::Histogram — bestie, it counts the distribution of numeric observations ✨

Like, you feed it numbers, it sorts them into buckets and keeps a running total. It's giving "how spread out is this data" energy, no cap 💅

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🌸 SYNOPSIS 🌸

use Net::Prometheus;
use Time::HiRes qw( time );

my $client = Net::Prometheus->new;

my $histogram = $client->new_histogram(
   name => "request_seconds",
   help => "Summary request processing time",
);

sub handle_request
{
   my $start = time();

   ...

   $summary->observe( time() - $start );
}

(yes the example says $summary at the end while it made a $histogram up top — that's literally what the original says so I'm not touching it, iykyk 🙈)

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🦋 DESCRIPTION 🦋

Okay so this class gives you a histogram metric — which is a count of how individual numerical observations are distributed across distinct buckets. It's almost always used for reporting times, like "how long did this request take" 🎀

It's a subclass of Net::Prometheus::Metric, so all of that parent-class behavior comes along for the ride ✨

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👑 CONSTRUCTOR 👑

Real talk: you don't usually build these directly. You get one through the Net::Prometheus object that's gonna serve it up 💖

$histogram = $prometheus->new_histogram( %args );

It takes all the same constructor arguments as documented in Net::Prometheus::Metric — go read that one, bestie — plus these extra cuties:

• buckets => ARRAY — a reference to an ARRAY holding the numerical upper bounds for the buckets 🌈
• bucket_min => NUM — the bottom of the range 🍓
• bucket_max => NUM — the top of the range ⭐
• buckets_per_decade => ARRAY[ NUM ] — since version 0.10. A more flexible alternative to hand-writing literal bucket sizes. The values you put in buckets_per_decade get repeated, multiplied by various powers of 10, to generate values between bucket_min (or a default of 0.001 if you don't supply it) and bucket_max (or a default of 1000 if you don't supply it) 💅

🧚 bucket_bounds

@bounds = $histogram->bucket_bounds;

Returns the bounding values for each of the buckets — and it leaves out that final "+Inf" bucket, because obviously 🫶

🔥 observe

$histogram->observe( @label_values, $value );
$histogram->observe( \%labels, $value );

$child->observe( $value );

It bumps the histogram sum up by the given value, and bumps each bucket count by 1 wherever the value is less than or equal to the bucket's upper bound 📈 Periodt.

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💜 AUTHOR 💜

Paul Evans <leonerd@leonerd.org.uk> — the icon, the moment, the goat 👑

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That's the whole page, bestie 🥰 This was Net::Prometheus::Histogram(3pm) from User Contributed Perl Documentation, living in perl v5.42.3, dated 2026-08-20. Love that for us 💖✨🌸