【发布时间】：2017-11-10 11:13:42
【问题描述】：
在迁移步骤中，我经常看到部署挂起。为 Tomcat 打包在 WAR 中的 Java/Scala 应用程序。数据库是使用 MariaDB 连接器 (https://downloads.mariadb.org/connector-java/) 的 RDS Aurora。
可能与 Flyway 无关，但获取连接是一个普遍问题。
迁移是从容器中的 shell 运行的：
java -cp `echo WEB-INF/lib/*|tr ' ' :` foo.Migrate
迁移代码如下：
def main(args: Array[String]): Unit = {
Environment.dbFlywayPassword.foreach { pass =>
val flyway = new Flyway
flyway.setDataSource(Environment.jdbcUrl, "flyway", pass)
flyway.migrate
}
}
连接字符串：
jdbc:mysql:aurora://%RDS_HOST%/xxx?serverSslCert=/rds-ca-2015-root.pem&useSSL=true&connectTimeout=10000
我尝试在 Flyway 中提高日志记录级别，但在此行之后没有记录任何内容：
15:57:35.115 [main] INFO o.f.c.internal.util.VersionPrinter - Flyway 4.2.0 by Boxfuse
所以我得到了一个线程转储，看起来像这样：
15:57:35.115 [main] INFO o.f.c.internal.util.VersionPrinter - Flyway 4.2.0 by Boxfuse
2017-06-08 15:57:56
Full thread dump OpenJDK 64-Bit Server VM (25.121-b13 mixed mode):
"MariaDb-failover-1" #8 daemon prio=5 os_prio=0 tid=0x00005555f80ae000 nid=0x14 waiting on condition [0x00007fc330b8f000]
java.lang.Thread.State: TIMED_WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000000f5c59b10> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"Service Thread" #7 daemon prio=9 os_prio=0 tid=0x00005555f70bf000 nid=0x12 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C1 CompilerThread1" #6 daemon prio=9 os_prio=0 tid=0x00005555f7063000 nid=0x11 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C2 CompilerThread0" #5 daemon prio=9 os_prio=0 tid=0x00005555f7060800 nid=0x10 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Signal Dispatcher" #4 daemon prio=9 os_prio=0 tid=0x00005555f705e800 nid=0xf waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Finalizer" #3 daemon prio=8 os_prio=0 tid=0x00005555f702f000 nid=0xe in Object.wait() [0x00007fc331616000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000000f5a30c58> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
- locked <0x00000000f5a30c58> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)
"Reference Handler" #2 daemon prio=10 os_prio=0 tid=0x00005555f702c000 nid=0xd in Object.wait() [0x00007fc331717000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000000f5a30e10> (a java.lang.ref.Reference$Lock)
at java.lang.Object.wait(Object.java:502)
at java.lang.ref.Reference.tryHandlePending(Reference.java:191)
- locked <0x00000000f5a30e10> (a java.lang.ref.Reference$Lock)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:153)
"main" #1 prio=5 os_prio=0 tid=0x00005555f6f85000 nid=0xb runnable [0x00007fc34341d000]
java.lang.Thread.State: RUNNABLE
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
at java.net.SocketInputStream.read(SocketInputStream.java:171)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at sun.security.ssl.InputRecord.readFully(InputRecord.java:465)
at sun.security.ssl.InputRecord.read(InputRecord.java:503)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:973)
- locked <0x00000000f0a66090> (a java.lang.Object)
at sun.security.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:930)
at sun.security.ssl.AppInputStream.read(AppInputStream.java:105)
- locked <0x00000000f0a81eb0> (a sun.security.ssl.AppInputStream)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
at java.io.BufferedInputStream.read1(BufferedInputStream.java:286)
at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
- locked <0x00000000f06b5118> (a java.io.BufferedInputStream)
at org.mariadb.jdbc.internal.io.input.StandardPacketInputStream.getPacketArray(StandardPacketInputStream.java:125)
at org.mariadb.jdbc.internal.io.input.StandardPacketInputStream.getPacket(StandardPacketInputStream.java:95)
at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.readPacket(AbstractQueryProtocol.java:1002)
at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.getResult(AbstractQueryProtocol.java:982)
at org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.readRequestSessionVariables(AbstractConnectProtocol.java:498)
at org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.readPipelineAdditionalData(AbstractConnectProtocol.java:544)
at org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connect(AbstractConnectProtocol.java:410)
at org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connect(AbstractConnectProtocol.java:357)
at org.mariadb.jdbc.internal.protocol.AuroraProtocol.loop(AuroraProtocol.java:149)
at org.mariadb.jdbc.internal.failover.impl.AuroraListener.reconnectFailedConnection(AuroraListener.java:179)
at org.mariadb.jdbc.internal.failover.impl.MastersSlavesListener.initializeConnection(MastersSlavesListener.java:154)
at org.mariadb.jdbc.internal.failover.FailoverProxy.<init>(FailoverProxy.java:94)
at org.mariadb.jdbc.internal.util.Utils.retrieveProxy(Utils.java:464)
at org.mariadb.jdbc.Driver.connect(Driver.java:103)
at org.flywaydb.core.internal.util.jdbc.DriverDataSource.getConnectionFromDriver(DriverDataSource.java:416)
at org.flywaydb.core.internal.util.jdbc.DriverDataSource.getConnection(DriverDataSource.java:381)
at org.flywaydb.core.internal.util.jdbc.JdbcUtils.openConnection(JdbcUtils.java:51)
at org.flywaydb.core.Flyway.execute(Flyway.java:1418)
at org.flywaydb.core.Flyway.migrate(Flyway.java:971)
at tgam.service.data.Migrate$.$anonfun$main$1(Migrate.scala:11)
at foo.Migrate$.$anonfun$main$1$adapted(Migrate.scala:8)
at foo.Migrate$$$Lambda$4/458209687.apply(Unknown Source)
at scala.Option.foreach(Option.scala:257)
at foo.Migrate$.main(Migrate.scala:8)
at foo.Migrate.main(Migrate.scala)
"VM Thread" os_prio=0 tid=0x00005555f7022000 nid=0xc runnable
"VM Periodic Task Thread" os_prio=0 tid=0x00005555f70da800 nid=0x13 waiting on condition
JNI global references: 232
Heap
def new generation total 4928K, used 1611K [0x00000000f0600000, 0x00000000f0b50000, 0x00000000f5950000)
eden space 4416K, 24% used [0x00000000f0600000, 0x00000000f0712c10, 0x00000000f0a50000)
from space 512K, 100% used [0x00000000f0a50000, 0x00000000f0ad0000, 0x00000000f0ad0000)
to space 512K, 0% used [0x00000000f0ad0000, 0x00000000f0ad0000, 0x00000000f0b50000)
tenured generation total 10944K, used 4187K [0x00000000f5950000, 0x00000000f6400000, 0x0000000100000000)
the space 10944K, 38% used [0x00000000f5950000, 0x00000000f5d66e78, 0x00000000f5d67000, 0x00000000f6400000)
Metaspace used 13061K, capacity 13306K, committed 13568K, reserved 1060864K
class space used 1381K, capacity 1449K, committed 1536K, reserved 1048576K
看起来 I/O 在 org.mariadb.jdbc.Driver.connect 中挂起，但我确实设置了 connectTimeout（10 秒）。这个超时似乎没有效果（我需要一个socketTimeout per https://github.com/brettwooldridge/HikariCP/issues/754 吗？）
这种情况已经发生了一段时间。当我使用 Tomcat 的 contextInitialized 钩子进行迁移时，也发生了同样的事情。我决定在启动 Tomcat 之前重构为一个单独的调用，这通常看起来是一个更好的主意，但它并没有影响这种行为。
通常会发生代码挂起，2-3 分钟后 ECS 将超时，并触发重新部署。在这些重试次数（例如最多 10 次）之后，Flyway 将成功运行并且服务将启动。
【问题讨论】：
标签： java mysql flyway rds amazon-ecs