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Date: Wed, 25 Mar 2009 19:28:12 -0700 (PDT)
From: "raghul@yahoo.com" <raghul@yahoo.com>
Subject: Incorrect implementation of QuorumCnxManager.haveDelivered()?
To: zookeeper-user@hadoop.apache.org
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Hello,=0A=0AI am a ZooKeeper newbie, so pardon me if I am repeating questio=
ns that have been raised before.=0A=0AI believe the implementation of Quoru=
mCnxManager.haveDelivered() is incorrect. If I understand correctly, queueS=
endMap contains a queue of messages for each peer to which the local peer i=
s trying to send election messages. When FastLeaderElection notices a timeo=
ut while polling for inbound messages, it checks to see if all the messages=
 have been delivered by calling this function. So shouldn't this function a=
ctually check each queue in the hash map and return true if all of them are=
 empty? This method is rather returning true the if just one of the queues =
is empty?=0A=0A    /**=0A     * Check if all queues are empty, indicating t=
hat all messages have been delivered.=0A     */=0A    boolean haveDelivered=
() {=0A        for (ArrayBlockingQueue<ByteBuffer> queue : queueSendMap.val=
ues()) {=0A            LOG.debug("Queue size: " + queue.size());=0A        =
    if (queue.size() =3D=3D 0)=0A                return true;=0A        }=
=0A=0A        return false;=0A    }=0A=0AAlso, could someone expain the rea=
son behind maitaining a queue of messages for each peer in queueSendMap? Wh=
y do we need a per peer queue here? Since this is used during election, the=
 local peer is not sending more than one message at a time to the remote pe=
er. So the hash map needs to store just one message per remote peer?=0A=0A-=
Raghu=0A=0A=0A=0A