使用Spark写入TiDB时，错误GC生存时间短于事务持续时间

Question

我正在使用Apache Spark批量写入数据。批次为1天。在运行火花作业时，我遇到了这个错误。我正在使用MySQL java连接器连接到TiDB集群。Spark为写作创建了144个并行任务。

java.sql.SQLException: GC life time is shorter than transaction duration
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3536)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3468)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1957)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2107)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2642)
at com.mysql.jdbc.ConnectionImpl.commit(ConnectionImpl.java:1610)
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:498)
at com.mysql.jdbc.LoadBalancingConnectionProxy.invoke(LoadBalancingConnectionProxy.java:359)
at com.sun.proxy.$Proxy13.commit(Unknown Source)
at org.apache.spark.sql.execution.datasources.jdbc.JdbcUtils$.savePartition(JdbcUtils.scala:665)
at org.apache.spark.sql.execution.datasources.jdbc.JdbcUtils$$anonfun$saveTable$1.apply(JdbcUtils.scala:821)
at org.apache.spark.sql.execution.datasources.jdbc.JdbcUtils$$anonfun$saveTable$1.apply(JdbcUtils.scala:821)
at org.apache.spark.rdd.RDD$$anonfun$foreachPartition$1$$anonfun$apply$29.apply(RDD.scala:929)
at org.apache.spark.rdd.RDD$$anonfun$foreachPartition$1$$anonfun$apply$29.apply(RDD.scala:929)
at org.apache.spark.SparkContext$$anonfun$runJob$5.apply(SparkContext.scala:2067)
at org.apache.spark.SparkContext$$anonfun$runJob$5.apply(SparkContext.scala:2067)
at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:87)
at org.apache.spark.scheduler.Task.run(Task.scala:109)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:345)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

Answer 1

此错误意味着Spark任务事务时间超过TiDB的GC Life Time，这意味着：

当前读取的数据已被TiDB删除，因为数据的使用寿命超过了配置的GC Life Time

因此解决方案可能会尝试将tikv_gc_life_time增加：

update mysql.tidb set variable_value='30m' where variable_name='tikv_gc_life_time';

查看更多：

https://github.com/pingcap/docs/blob/master/op-guide/gc.md#configuration-并监控