my @hours;
while ( <$file> ) {
    my $hour = ( localtime )[ 2 ];

    if ( /(job-id-format) failed/ ) {
        if ( ! exists $failed{ $1 } ) {
            push @{ $hours[ $hour ] }, $1;
            failed{ $1 } = 1;
        }
        report_temporary_job_failure( $1 );
    } elsif ( /(job-id-format) succeeded/ ) {
        delete $failed{ $1 } if exists $failed{ $1 };
        report_previously_failed_job_success( $1 );
    }
    if ( 0 == $. % 100  ) {
        my $purge = ( $hour - 8 >= 0 ) ?
            $hour - 8 : $hour + 24 - 8;
        while ( $job = shift @{ $hours[ $purge ] } ) {
            report_final_job_failure( $job );
            delete $failed{ $job };
        }
    }
}