CommunicationsException: Communications link failure - java

I used java to query some records from Mysql. But in some querys of one duration, i meet a problem which make query failed, but in others , it query successful. The error message is next:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 90 milliseconds ago. The last packet sent successfully to the server was 1,674 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3090)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2979)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3520)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:935)
at com.mysql.jdbc.MysqlIO.nextRow(MysqlIO.java:1433)
at com.mysql.jdbc.MysqlIO.readSingleRowSet(MysqlIO.java:2924)
at com.mysql.jdbc.MysqlIO.getResultSet(MysqlIO.java:477)
at com.mysql.jdbc.MysqlIO.readResultsForQueryOrUpdate(MysqlIO.java:2619)
at com.mysql.jdbc.MysqlIO.readAllResults(MysqlIO.java:1788)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2209)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2619)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2569)
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1521)
......
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:58)
Caused by: java.io.IOException: Packets received out of order
at com.mysql.jdbc.MysqlIO.readRemainingMultiPackets(MysqlIO.java:3152)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3077)
... 23 more
I have tried some method, such like:
set max_allowed_packet = 128 * 1024 * 1024 in /etc/my.conf
add ?autoReconnect=true&failOverReadOnly=false&maxReconnects=10 to my connection url
but nothing happens.
My environments is:
Mysql: 5.5.3-m3-log Source distribution
Java: 1.6.0_16
Jdk: HotSpot(TM) 64-Bit Server VM (build 14.2-b01, mixed mode)
JDBC: mysql-connector-java-5.1.18

The problem are solved.
It is because the result is too huge. In my query , i used the default cursor, which is client-side cursors, This means, the whole resultant recordset of a SELECT is returned to the client (application) and the paging is done there. So the total result set is too big and make jdbc client out of memory.
The solution is that:
add "useCursorFetch=true" to JDBC URL configuration parameters
call statement.setFetchSize(100)
You can read more detail from : http://wiki.gxtechnical.com/commwiki/servlet/hwiki?Client%20and%20server%20cursors%20-%20using%20MySQL

This might happen when you try to commit with stale connection. Try checking for the connection state before doing the commit.

Related

Communications link failure occurs while communicating with MYSQL server using TimerTask [duplicate]

This question already has answers here:
Official reasons for "Software caused connection abort: socket write error"
(14 answers)
Closed 5 years ago.
all.
I have encounter the problem for some days, this is the detail stack information:
org.springframework.dao.RecoverableDataAccessException:
### Error updating database. Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 18,940 milliseconds ago. The last packet sent successfully to the server was 18,918 milliseconds ago.
### The error may involve com.tuan800.searchtask.model.dao.mybatis.RelationDao.updateSuggest-Inline
### The error occurred while setting parameters
### Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 18,940 milliseconds ago. The last packet sent successfully to the server was 18,918 milliseconds ago.
; SQL []; Communications link failure
The last packet successfully received from the server was 18,940 milliseconds ago. The last packet sent successfully to the server was 18,918 milliseconds ago.; nested exception is com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 18,940 milliseconds ago. The last packet sent successfully to the server was 18,918 milliseconds ago.
at org.springframework.jdbc.support.SQLExceptionSubclassTranslator.doTranslate(SQLExceptionSubclassTranslator.java:98)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:72)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:71)
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:346)
at $Proxy10.update(Unknown Source)
at org.mybatis.spring.SqlSessionTemplate.update(SqlSessionTemplate.java:245)
at com.tuan800.searchtask.model.dao.mybatis.impl.RelationDaoImpl.updateSuggest(RelationDaoImpl.java:24)
at com.tuan800.searchtask.service.impl.RelationServiceImpl.modifyRelationCount(RelationServiceImpl.java:64)
at com.tuan800.searchtask.RelationIndexTask.main(RelationIndexTask.java:33)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:115)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 18,940 milliseconds ago. The last packet sent successfully to the server was 18,918 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1118)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3055)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2941)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3489)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1959)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2113)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2568)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2113)
at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1364)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.execute(NewProxyPreparedStatement.java:989)
at sun.reflect.GeneratedMethodAccessor163.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.ibatis.logging.jdbc.PreparedStatementLogger.invoke(PreparedStatementLogger.java:45)
at $Proxy20.execute(Unknown Source)
at org.apache.ibatis.executor.statement.PreparedStatementHandler.update(PreparedStatementHandler.java:22)
at org.apache.ibatis.executor.statement.RoutingStatementHandler.update(RoutingStatementHandler.java:51)
at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:29)
at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:88)
at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:121)
at sun.reflect.GeneratedMethodAccessor165.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:338)
... 10 more
Caused by: java.net.SocketException: Software caused connection abort: recv failed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:129)
at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:114)
at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:161)
at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:189)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2499)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2952)
... 32 more
I want update a record in mysql by mybatis and spring,and I update it one by one,below is mybatis config:
update suggestions set count = #{count},version=#{version},freq=#{freq} where id = #{id}
And the service code:
for(RelationBvo relation : list){
Long totalCount = solrDealService.queryResult(relation.getWord(),null,null,0);
relation.setCount(totalCount.intValue());
if(relation.getFreq() == 0){
relation.setFreq(1);
}
***relationDao.updateSuggest(relation);//update record***
executedCount++;
logger.info("Program have executed "+executedCount+" records.");
}
can anyone help me?thanks very much.
Your mySQL connections are timing out before your connection pool recognizes them. There are multiple ways to fix this:
Increase the timeout value in mysql config file (my.ini)
Reduce the idle time in your connection pool, so that it will discard the connection before mysql will close it
Add a validate connection query in your pool config so that the pool tests each connection before it gives it to you, but this can slow down the system terribly.

VoltDB Timeout for createConnection

Below is a simple code snippet that shows how to connect to a VoltDB server.
ClientConfig clientConfig = new ClientConfig();
Client client = ClientFactory.createClient(clientConfig);
String server = "192.168.43.32";
client.createConnection(server);
Based on my experiments, if the server is down or just not connectable from network layer, it will take about 75 seconds to get the response.
SEVERE: Failed to connect to 192.168.43.32, in 75,359 ms
java.net.ConnectException: Operation timed out
at sun.nio.ch.Net.connect0(Native Method)
at sun.nio.ch.Net.connect(Net.java:458)
at sun.nio.ch.Net.connect(Net.java:450)
at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:648)
at java.nio.channels.SocketChannel.open(SocketChannel.java:189)
at org.voltdb.client.ConnectionUtil.getAuthenticatedConnection(ConnectionUtil.java:154)
at org.voltdb.client.ConnectionUtil.getAuthenticatedConnection(ConnectionUtil.java:142)
at org.voltdb.client.ConnectionUtil.getAuthenticatedConnection(ConnectionUtil.java:134)
at org.voltdb.client.Distributer.createConnectionWithHashedCredentials(Distributer.java:878)
at org.voltdb.client.ClientImpl.createConnectionWithHashedCredentials(ClientImpl.java:189)
at org.voltdb.client.ClientImpl.createConnection(ClientImpl.java:682)
at src.java.tutorial.voltdb.integration.ConnectionTest.main(ConnectionTest.java:27)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
Is there any ways to set the time out time, so the application needs not to wait for such a long time. A successful connection normally takes just tens of milliseconds, so I think if the connection cannot be established within 1000 milliseconds, something is definitely wrong already.
I have tried the setting of below
clientConfig.setConnectionResponseTimeout(1000);
In this case, it has no effects at all. So I guess it is not for this purpose.
Normally when the database is down and your client tries to connect it will get an immediate Connection refused exception, for example:
Exception in thread "main" java.net.ConnectException: Connection refused
at sun.nio.ch.Net.connect0(Native Method)
at sun.nio.ch.Net.connect(Net.java:364)
at sun.nio.ch.Net.connect(Net.java:356)
at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:623)
at java.nio.channels.SocketChannel.open(SocketChannel.java:184)
at org.voltdb.client.ConnectionUtil.getAuthenticatedConnection(ConnectionUtil.java:165)
at org.voltdb.client.ConnectionUtil.getAuthenticatedConnection(ConnectionUtil.java:153)
at org.voltdb.client.ConnectionUtil.getAuthenticatedConnection(ConnectionUtil.java:145)
at org.voltdb.client.Distributer.createConnectionWithHashedCredentials(Distributer.java:890)
at org.voltdb.client.ClientImpl.createConnectionWithHashedCredentials(ClientImpl.java:191)
at org.voltdb.client.ClientImpl.createConnection(ClientImpl.java:684)
at benchmark.Benchmark.<init>(Benchmark.java:17)
at benchmark.Benchmark.main(Benchmark.java:78)
In general, a "java.net.ConnectException: Connection timed out" can occur if there is a firewall that prevents the client from receiving any sort of response, or there could be other causes. The first thing to check might be if you have any firewall or network settings that would prevent access to port 21212 (the default VoltDB database connection port).
The ClientConfig setConnectionResponseTimeout() setting is used to cause a live connection to be closed if it hasn't received a response from a procedure call or a ping for the given number of milliseconds, but it is not used for creating a new connection.

Packets received out of order with large ResultSet from MySQL, JDBC

I have a problem, which I have not been able to resolve for a couple of days now.. So, i'm trying to list a large resultset row by row with the solution, cited multiple times on the internets, including stackoverflow:
Statement stmt = readOnlyConn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_READ_ONLY);
stmt.setFetchSize(Integer.MIN_VALUE);
and it seems to work. At least for some time (it writes out the lines into a text file) until I get the error below. I have googled my eyes out trying to find what could be causing this, tried some mysql server tweaks, nothing works. Can anyone please help me? Everyone keeps reporting splendid results with the solution above, but it seems to hate me in particular.. I would greatly appreciate any help.
java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 15 milliseconds ago. The last packet sent successfully to the server was 6,239 milliseconds ago.
at gblaster.main.lambda$main$1(main.java:134)
at gblaster.main$$Lambda$3/792791759.accept(Unknown Source)
at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1359)
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580)
at gblaster.main.main(main.java:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 15 milliseconds ago. The last packet sent successfully to the server was 6,239 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1129)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3720)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3609)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4160)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:928)
at com.mysql.jdbc.MysqlIO.nextRow(MysqlIO.java:2053)
at com.mysql.jdbc.MysqlIO.readSingleRowSet(MysqlIO.java:3554)
at com.mysql.jdbc.MysqlIO.getResultSet(MysqlIO.java:491)
at com.mysql.jdbc.MysqlIO.readResultsForQueryOrUpdate(MysqlIO.java:3245)
at com.mysql.jdbc.MysqlIO.readAllResults(MysqlIO.java:2413)
at com.mysql.jdbc.ServerPreparedStatement.serverExecute(ServerPreparedStatement.java:1500)
at com.mysql.jdbc.ServerPreparedStatement.executeInternal(ServerPreparedStatement.java:857)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2313)
at db.mysql.GMySQLConnector.loadAllOrfsForGenomeId(GMySQLConnector.java:296)
at gblaster.deploy.Deployer.unloadORFsForGenomeToFile(Deployer.java:124)
at gblaster.main.lambda$main$1(main.java:128)
... 9 more
Caused by: java.io.IOException: Packets received out of order
at com.mysql.jdbc.MysqlIO.readRemainingMultiPackets(MysqlIO.java:3782)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3707)
... 23 more
Your code is difficult to understand because Integer.MIN_VALUE is negative,
stmt.setFetchSize(Integer.MIN_VALUE);
I think you'll find it works much better with
stmt.setFetchSize(100); // <-- I also bet this works better then 1.
Finally, the Statement.setFetchSize(int) javadoc says (emphasis added),
Throws:
SQLException - if a database access error occurs, this method is called on a closed Statement or the condition rows >= 0 is not satisfied.
So you should be getting a SQLException with your code.

odd SQLException - Could not retrieve transation read-only status server

I have a Quartz Job that executes a Stored Procedure in my MySQL database once every 5 minutes, and for some reason, 1 out of 3 executions fails and gives this weird exception. I have searched and searched for what this exception means, but I could not find a solution. Here is the full stack trace:
java.sql.SQLException: Could not retrieve transation read-only status server
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1078)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:975)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:920)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:951)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:941)
at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3939)
at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3910)
at com.mysql.jdbc.PreparedStatement.checkReadOnlySafeStatement(PreparedStatement.java:1258)
at com.mysql.jdbc.CallableStatement.checkReadOnlySafeStatement(CallableStatement.java:2656)
at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1278)
at com.mysql.jdbc.CallableStatement.execute(CallableStatement.java:920)
at com.mchange.v2.c3p0.impl.NewProxyCallableStatement.execute(NewProxyCallableStatement.java:3044)
at org.deadmandungeons.website.tasks.RankUpdateTask.execute(RankUpdateTask.java:30)
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:573)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 1,198,219 milliseconds ago. The last packet sent successfully to the server was 950,420 milliseconds ago.
at sun.reflect.GeneratedConstructorAccessor43.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3673)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3562)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4113)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2812)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2761)
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1612)
at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3933)
... 9 more
Caused by: java.net.SocketException: Connection timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:150)
at java.net.SocketInputStream.read(SocketInputStream.java:121)
at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:114)
at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:161)
at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:189)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3116)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3573)
... 17 more
So I figured it is timing out because it thinks the MySQL server is in read-only status?
This only happens for this quartz job, and not any other time when I communicate with the database. This execution is of course happening in another thread, but I don't think that would have anything to do with it.
Why would it think the server was in read-only mode?
Also, I don't think "transation" is a word, so there's that...
Sorry for posting on old thread,
As stack trace says
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
This implies the link between JDBC and DB is broken.As per your observation you say 1 out of 3 job invocations fails.
You have these jobs scheduled every 5 minutes and as per trace the last successful message sent to server is ~15 minutes before.
Hence I suspect either
You are procedure is not returning (waiting on something)
The JDBC connection has been invalidated by the firewall/ proxy
It will interesting to see the how connections are managed, As per logs I see you are using c3p0.
You can try setting unreturnedConnectionTimeout and debugUnreturnedConnectionStackTraces. This will give you more insight into connection leaks or db calls which are taking long.
Research takes nowhere, as you guys said, but the error shows what seems to be a Database being populated by two applications at the same time.
Do you have admin privileges on this MySQL server? If you do, you should try setting
FLUSH TABLES WITH READ LOCK;
SET GLOBAL READ_ONLY=ON;
as a test to reproduce the error. Just to warn you, this command makes your database unwritable, so you will not be able to add data in it until you revert this configuration, obviously with
SET GLOBAL READ_ONLY=0;
UNLOCK TABLES;
If the result of this test is positive (same error had been reproduced), you should try isolating applications that are storing data on your database, to find out which one is conflicting with Quartz.
I'm sorry for being vague, but I hope it gives you some help...

Java BoneCP MySQL connection timing out

I have an application set up to pool mysql connections with BoneCP. Right now, the application isn't getting a ton of use, so the connections aren't used as frequently. After a certain amount of time, queries that once worked, start to fail, and I get messages similar to this:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 2,618,063 milliseconds ago. The last packet sent successfully to the server was 44,734 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1117)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3567)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3456)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3997)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2468)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2629)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2719)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1379)
at com.jolbox.bonecp.PreparedStatementHandle.execute(PreparedStatementHandle.java:138)
I am setting up BoneCP like this:
BoneCPConfig config = new BoneCPConfig();
config.setJdbcUrl("jdbc:mysql://" + hostname + "/" + database);
config.setUsername(username);
config.setPassword(password);
config.setMinConnectionsPerPartition(minPoolSize);
config.setMaxConnectionsPerPartition(maxPoolSize);
config.setIdleConnectionTestPeriodInMinutes(60);
config.setIdleMaxAgeInMinutes(240);
config.setPartitionCount(1);
connectionPool = new BoneCP(config);
I'm unsure of how to find out what the timeout is for the mysql server (it hasn't been changed from whatever the default is), but I get this error after around 5 or 10 mins of no connection pool activity, which seems extremely short.
Either you'll have to configure mysqls idle timeout (setting wait_timeout = X / interactive_timeout = X), or you could configure the connection pool to issue keep-alive statements:
config.setIdleConnectionTestPeriodInMinutes(10);
config.setConnectionTestStatement("/* ping */ SELECT 1"):

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