Return-Path: X-Original-To: apmail-cassandra-commits-archive@www.apache.org Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 554B3FE66 for ; Tue, 26 Mar 2013 11:45:17 +0000 (UTC) Received: (qmail 88438 invoked by uid 500); 26 Mar 2013 11:45:17 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 88318 invoked by uid 500); 26 Mar 2013 11:45:16 -0000 Mailing-List: contact commits-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@cassandra.apache.org Delivered-To: mailing list commits@cassandra.apache.org Received: (qmail 88296 invoked by uid 99); 26 Mar 2013 11:45:16 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 26 Mar 2013 11:45:16 +0000 Date: Tue, 26 Mar 2013 11:45:15 +0000 (UTC) From: "Sylvain Lebresne (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (CASSANDRA-5382) ConcurrentModificantionException on server when multiple CQL3 read requests received on single column family simultaneously. 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/CASSANDRA-5382?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Sylvain Lebresne updated CASSANDRA-5382: ---------------------------------------- Attachment: 0001-Copy-ResultSet-in-makeCountResult.txt >From a quick check the only place I see the metadata list being modified after Metadata creation is in makeCountResult. Even if I've missed another spot, not copying in makeCountResult was bad so attaching a simple patch to fix that. > ConcurrentModificantionException on server when multiple CQL3 read requests received on single column family simultaneously. > ---------------------------------------------------------------------------------------------------------------------------- > > Key: CASSANDRA-5382 > URL: https://issues.apache.org/jira/browse/CASSANDRA-5382 > Project: Cassandra > Issue Type: Bug > Affects Versions: 1.2.3 > Environment: SLES, Sun JDK 1.6.0_43 > Reporter: Jason Reber > Priority: Minor > Attachments: 0001-Copy-ResultSet-in-makeCountResult.txt > > > The exception below is thrown on the server when two reads are performed at the exact same time on the same column family. This causes the query to fail. > The problem appears to be caused by the 'name' list in org.apache.cassandra.cql3.ResultSet$Metadata. The reference is passed in to the constructor and iterated without copying and without a synch block. When two of these ResultSet instances are created from the same metadata list at the same time, a ConcurrentModificationException is thrown. > The error: > ERROR [Thrift:860] 2013-03-25 09:27:39,467 CustomTThreadPoolServer.java (line 217) Error occurred during processing of message. > java.util.ConcurrentModificationException > at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372) > at java.util.AbstractList$Itr.next(AbstractList.java:343) > at org.apache.cassandra.cql3.ResultSet$Metadata.allInSameCF(ResultSet.java:237) > at org.apache.cassandra.cql3.ResultSet$Metadata.(ResultSet.java:219) > at org.apache.cassandra.cql3.ResultSet.(ResultSet.java:47) > at org.apache.cassandra.cql3.statements.Selection$ResultSetBuilder.(Selection.java:239) > at org.apache.cassandra.cql3.statements.Selection$ResultSetBuilder.(Selection.java:221) > at org.apache.cassandra.cql3.statements.Selection.resultSetBuilder(Selection.java:211) > at org.apache.cassandra.cql3.statements.SelectStatement.process(SelectStatement.java:655) > at org.apache.cassandra.cql3.statements.SelectStatement.processResults(SelectStatement.java:147) > at org.apache.cassandra.cql3.statements.SelectStatement.execute(SelectStatement.java:136) > at org.apache.cassandra.cql3.statements.SelectStatement.execute(SelectStatement.java:62) > at org.apache.cassandra.cql3.QueryProcessor.processStatement(QueryProcessor.java:132) > at org.apache.cassandra.cql3.QueryProcessor.processPrepared(QueryProcessor.java:254) > at org.apache.cassandra.thrift.CassandraServer.execute_prepared_cql3_query(CassandraServer.java:1851) > at org.apache.cassandra.thrift.Cassandra$Processor$execute_prepared_cql3_query.getResult(Cassandra.java:4166) > at org.apache.cassandra.thrift.Cassandra$Processor$execute_prepared_cql3_query.getResult(Cassandra.java:4154) > at org.apache.thrift.ProcessFunction.process(ProcessFunction.java:32) > at org.apache.thrift.TBaseProcessor.process(TBaseProcessor.java:34) > at org.apache.cassandra.thrift.CustomTThreadPoolServer$WorkerProcess.run(CustomTThreadPoolServer.java:199) > at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895) > at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918) > at java.lang.Thread.run(Thread.java:662) -- This message is automatically generated by JIRA. 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