def heartbeat_check():
'''
Find the node with the oldest hearbeat timestamp and query it
'''
logging.debug('DEBUG: heartbeat_check()')
siblings = Sibling.objects.filter().order_by('last_heartbeat')
if siblings:
oldest = siblings[0]
try:
lock = Lock.acquire_lock(u''.join(['heartbeat_check', oldest.uuid]), 20)
node = RemoteCall(uuid=oldest.uuid)
oldest.last_heartbeat = datetime.datetime.now()
response = node.heartbeat()
oldest.cpuload = int(float(response['cpuload']))
oldest.status = NODE_STATUS_UP
oldest.failure_count = 0
oldest.save()
lock.release()
except LockError:
pass
except HeartbeatError:
oldest.status = NODE_STATUS_DOWN
oldest.failure_count += 1
oldest.save()
if oldest.failure_count > HEARTBEAT_FAILURE_THRESHOLD:
oldest.delete()
lock.release()
