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NAME

    Algorithm::Backoff::RetryTimeouts - A backoff-style retry algorithm
    with adjustable timeout support

VERSION

    version v1.0.0

SYNOPSIS

        use Algorithm::Backoff::RetryTimeouts;
    
        my $retry_algo = Algorithm::Backoff::RetryTimeouts->new(
            # common adjustments (defaults shown)
            max_attempts          => 8,
            max_actual_duration   => 50,
            jitter_factor         => 0.1,
            timeout_jitter_factor => 0.1,
            adjust_timeout_factor => 0.5,
            min_adjust_timeout    => 5,
    
            # other defaults
            initial_delay         => sqrt(2),
            exponent_base         => sqrt(2),
            delay_on_success      => 0,
            min_delay             => 0,
            max_delay             => undef,
            consider_actual_delay => 1,
        );
    
        my ($delay, $timeout);
        $timeout = $retry_algo->timeout;
    
        my $is_successful = 0;
        while (!$is_successful) {
            $actionee->timeout( $timeout );
            $is_successful = $actionee->do_the_thing;
    
            ($delay, $timeout) = $is_successful ? $retry_algo->success : $retry_algo->failure;
            die "Ran out of time" if $delay == -1;
            sleep $delay;
        }

DESCRIPTION

    This module is a subclass of Algorithm::Backoff::Exponential that adds
    support for adjustable timeouts during each retry. This also comes with
    a sane set of defaults as a good baseline for most kinds of retry
    operations.

    A combination of features solves for most problems that would arise
    from retry operations:

      * Maximum attempts - Forces the algorithm to give up if repeated
      attempts don't yield success.

      * Maximum duration - Forces the algorithm to give up if no successes
      happen within a certain time frame.

      * Exponential backoff - A sqrt(2) exponential delay keeps single
      retries from waiting too long, while spreading out repeated retries
      that may fail too quickly and run out of max attempts. This also
      decreases the congestion that happens with repeated attempts.

      * Jitter - Adding random jitter to the retry delays solves for the
      Thundering Herd problem.

      * Adjustable timeouts - Providing an adjustable timeout after each
      request solves the opposite problem of exponential backoffs: slower,
      unresponsive errors that gobble up all of the max duration time in
      one go. Each new timeout is a certain percentage of the time left.

 Typical scenario