From dev-return-69602-archive-asf-public=cust-asf.ponee.io@zookeeper.apache.org Thu May 10 08:29:10 2018 Return-Path: X-Original-To: archive-asf-public@cust-asf.ponee.io Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by mx-eu-01.ponee.io (Postfix) with SMTP id DA52418063A for ; Thu, 10 May 2018 08:29:09 +0200 (CEST) Received: (qmail 99868 invoked by uid 500); 10 May 2018 06:29:08 -0000 Mailing-List: contact dev-help@zookeeper.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@zookeeper.apache.org Delivered-To: mailing list dev@zookeeper.apache.org Received: (qmail 99857 invoked by uid 99); 10 May 2018 06:29:08 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd1-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 10 May 2018 06:29:08 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd1-us-west.apache.org (ASF Mail Server at spamd1-us-west.apache.org) with ESMTP id CC94FC7BE7 for ; Thu, 10 May 2018 06:29:07 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd1-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: -109.501 X-Spam-Level: X-Spam-Status: No, score=-109.501 tagged_above=-999 required=6.31 tests=[ENV_AND_HDR_SPF_MATCH=-0.5, KAM_ASCII_DIVIDERS=0.8, RCVD_IN_DNSWL_MED=-2.3, SPF_PASS=-0.001, USER_IN_DEF_SPF_WL=-7.5, USER_IN_WHITELIST=-100] autolearn=disabled Received: from mx1-lw-eu.apache.org ([10.40.0.8]) by localhost (spamd1-us-west.apache.org [10.40.0.7]) (amavisd-new, port 10024) with ESMTP id CGkn39T9d2OM for ; Thu, 10 May 2018 06:29:06 +0000 (UTC) Received: from mailrelay1-us-west.apache.org (mailrelay1-us-west.apache.org [209.188.14.139]) by mx1-lw-eu.apache.org (ASF Mail Server at mx1-lw-eu.apache.org) with ESMTP id 685045F5B1 for ; Thu, 10 May 2018 06:29:06 +0000 (UTC) Received: from jira-lw-us.apache.org (unknown [207.244.88.139]) by mailrelay1-us-west.apache.org (ASF Mail Server at mailrelay1-us-west.apache.org) with ESMTP id 946CDE0F61 for ; Thu, 10 May 2018 06:29:00 +0000 (UTC) Received: from jira-lw-us.apache.org (localhost [127.0.0.1]) by jira-lw-us.apache.org (ASF Mail Server at jira-lw-us.apache.org) with ESMTP id 4F4A121298 for ; Thu, 10 May 2018 06:29:00 +0000 (UTC) Date: Thu, 10 May 2018 06:29:00 +0000 (UTC) From: "Hudson (JIRA)" To: dev@zookeeper.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (ZOOKEEPER-2959) ignore accepted epoch and LEADERINFO ack from observers when a newly elected leader computes new epoch MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/ZOOKEEPER-2959?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16469973#comment-16469973 ] Hudson commented on ZOOKEEPER-2959: ----------------------------------- FAILURE: Integrated in Jenkins build ZooKeeper-trunk #18 (See [https://builds.apache.org/job/ZooKeeper-trunk/18/]) ZOOKEEPER-2959: ignore accepted epoch and LEADERINFO ack from observers (ashraer: rev 088dfdf188663f6bad79b0e87b710737b318537d) * (edit) src/java/main/org/apache/zookeeper/server/quorum/LearnerHandler.java * (edit) src/java/test/org/apache/zookeeper/server/quorum/Zab1_0Test.java * (edit) src/java/main/org/apache/zookeeper/server/quorum/Leader.java * (add) src/java/test/org/apache/zookeeper/server/quorum/ZabUtils.java * (add) src/java/test/org/apache/zookeeper/server/quorum/LeaderWithObserverTest.java > ignore accepted epoch and LEADERINFO ack from observers when a newly elected leader computes new epoch > ------------------------------------------------------------------------------------------------------ > > Key: ZOOKEEPER-2959 > URL: https://issues.apache.org/jira/browse/ZOOKEEPER-2959 > Project: ZooKeeper > Issue Type: Bug > Affects Versions: 3.4.10, 3.5.3 > Reporter: xiangyq000 > Assignee: Bogdan Kanivets > Priority: Blocker > Fix For: 3.5.4, 3.6.0, 3.4.13 > > > Once the ZooKeeper cluster finishes the election for new leader, all learners report their accepted epoch to the leader for the computation of new cluster epoch. > org.apache.zookeeper.server.quorum.Leader#getEpochToPropose > {code:java} > private final HashSet connectingFollowers = new HashSet(); > public long getEpochToPropose(long sid, long lastAcceptedEpoch) throws InterruptedException, IOException { > synchronized(connectingFollowers) { > if (!waitingForNewEpoch) { > return epoch; > } > if (lastAcceptedEpoch >= epoch) { > epoch = lastAcceptedEpoch+1; > } > connectingFollowers.add(sid); > QuorumVerifier verifier = self.getQuorumVerifier(); > if (connectingFollowers.contains(self.getId()) && > verifier.containsQuorum(connectingFollowers)) { > waitingForNewEpoch = false; > self.setAcceptedEpoch(epoch); > connectingFollowers.notifyAll(); > } else { > long start = Time.currentElapsedTime(); > long cur = start; > long end = start + self.getInitLimit()*self.getTickTime(); > while(waitingForNewEpoch && cur < end) { > connectingFollowers.wait(end - cur); > cur = Time.currentElapsedTime(); > } > if (waitingForNewEpoch) { > throw new InterruptedException("Timeout while waiting for epoch from quorum"); > } > } > return epoch; > } > } > {code} > The computation will get an outcome once : > # The leader has call method "getEpochToPropose" > # The number of all reporters is greater than half of participants. > The problem is, an observer server will also send its accepted epoch to the leader, while this procedure treat observers as participants. > Supposed that the cluster consists of 1 leader, 2 followers and 1 observer, and now the leader and the observer have reported their accepted epochs while neither of the followers has. Thus, the connectingFollowers set consists of two elements, resulting in a size of 2, which is greater than half quorum, namely, 2. Then QuorumVerifier#containsQuorum will return true, because it does not check whether the elements of the parameter are participants. > The same flaw exists in org.apache.zookeeper.server.quorum.Leader#waitForEpochAck -- This message was sent by Atlassian JIRA (v7.6.3#76005)