Package org.jgroups.protocols

Class TIME

java.lang.Object
org.jgroups.stack.Protocol
org.jgroups.protocols.TIME
All Implemented Interfaces:
Lifecycle
public class TIME extends Protocol
Protocol measuring delivery times. Can be used in the up or down direction JIRA: https://issues.redhat.com/browse/JGRP-2101
Since:
4.0

  • Field Details

    • up_delivery_msgs

      protected final AverageMinMax up_delivery_msgs

    • up_delivery_batches

      protected final AverageMinMax up_delivery_batches

    • avg_up_batch_size

      protected final AverageMinMax avg_up_batch_size

    • down_delivery

      protected final AverageMinMax down_delivery

    • down_msgs

      protected boolean down_msgs

    • up_batches

      protected boolean up_batches

    • up_msgs

      protected boolean up_msgs

  • Constructor Details

    • TIME

      public TIME()

  • Method Details

    • resetStats

      public void resetStats()
      Overrides:
      resetStats in class Protocol

    • down

      public Object down(Message msg)
      Description copied from class: Protocol
      A message is sent down the stack. Protocols may examine the message and do something (e.g. add a header) with it, before passing it down.
      Overrides:
      down in class Protocol

    • up

      public Object up(Message msg)
      Description copied from class: Protocol
      A single message was received. Protocols may examine the message and do something (e.g. add a header) with it before passing it up.
      Overrides:
      up in class Protocol

    • up

      public void up(MessageBatch batch)
      Dividing the delivery time for a batch by the batch size is problematic, e.g. if a batch of 5 is received at time 0 and the 5 messages are delivered at times 20, 40, 60, 80 and 100, then the total time is 100, divided by 5 would be 20 per message.

      However, this is incorrect as it ignores the waiting times for the individual messages: e.g. message 3 gets delayed for 60 until it is processed.

      The correct average delivery time per message is therefore (20+40+60+80+100)/5 = 60.

      The above computation is not correct: we don't know whether a protocol looks at all messages: it may even remove some (making 'size' incorrect)!

      Also, we don't know whether messages in a batch are processed in order, on by one, or whether they are processed in parallel. Therefore, times for individual messages will not be computed.

      Overrides:
      up in class Protocol
      Parameters:
      batch - The message batch

    • avgTimePerMessageIncludingDelay

      protected static double avgTimePerMessageIncludingDelay(int num, long time)

    • add

      protected static void add(AverageMinMax avg, long num)