def gather_service_class_stats()

in redshift_monitoring.py [0:0]

• 37 lines of code
• 2 McCabe index (conditional complexity)

def gather_service_class_stats(cursor, cluster):
    metrics = []
    runtime = run_command(cursor,'''
        SELECT DATE_TRUNC('hour', a.service_class_start_time) AS metrics_ts,
               TRIM(d.name) as service_class, 
               COUNT(a.query) AS query_count,
               SUM(a.total_exec_time) AS sum_exec_time,
               sum(case when a.total_queue_time > 0 then 1 else 0 end) count_queued_queries,
               SUM(a.total_queue_time) AS sum_queue_time,        
               count(c.is_diskbased) as count_diskbased_segments
        FROM stl_wlm_query a 
        JOIN stv_wlm_classification_config b ON a.service_class = b.action_service_class
        LEFT OUTER JOIN (select query, SUM(CASE when is_diskbased = 't' then 1 else 0 end) is_diskbased 
                         from svl_query_summary 
                         group by query) c on a.query = c.query
        JOIN stv_wlm_service_class_config d on a.service_class = d.service_class
        WHERE a.service_class > 5
          AND a.service_class_start_time > DATEADD(hour, -2, current_date)
        GROUP BY DATE_TRUNC('hour', a.service_class_start_time),
                 d.name
    ''')
    service_class_info = cursor.fetchall()

    def add_metric(metric_name, service_class_id, metric_value, ts):
        metrics.append({
            'MetricName': metric_name,
            'Dimensions': [{'Name': 'ClusterIdentifier', 'Value': cluster},
                           {'Name': 'ServiceClassID', 'Value': str(service_class_id)}],
            'Timestamp': ts,
            'Value': metric_value
        })

    for service_class in service_class_info:
        add_metric('ServiceClass-Queued', service_class[1], service_class[4], service_class[0])
        add_metric('ServiceClass-QueueTime', service_class[1], service_class[5], service_class[0])
        add_metric('ServiceClass-Executed', service_class[1], service_class[2], service_class[0])
        add_metric('ServiceClass-ExecTime', service_class[1], service_class[3], service_class[0])
        add_metric('ServiceClass-DiskbasedQuerySegments', service_class[1], service_class[6], service_class[0])

    return metrics