你好，我在尝试在配置单元中启动select count（*）时遇到此错误。

Vertex failed, vertexName=Map 1, vertexId=vertex_1468250226607_1410_1_00, diagnostics=[Task failed, taskId=task_1468250226607_1410_1_00_000000, diagnostics=[TaskAttempt 0 failed, info=[Error: Failure while running task:java.lang.RuntimeException: org.apache.tez.dag.api.TezUncheckedException: Expected length: 8417166 actual length: 9223372036854775675
    at org.apache.hadoop.hive.ql.exec.tez.TezProcessor.initializeAndRunProcessor(TezProcessor.java:171)
    at org.apache.hadoop.hive.ql.exec.tez.TezProcessor.run(TezProcessor.java:137)
    at org.apache.tez.runtime.LogicalIOProcessorRuntimeTask.run(LogicalIOProcessorRuntimeTask.java:344)
    at org.apache.tez.runtime.task.TezTaskRunner$TaskRunnerCallable$1.run(TezTaskRunner.java:179)
    at org.apache.tez.runtime.task.TezTaskRunner$TaskRunnerCallable$1.run(TezTaskRunner.java:171)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:422)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
    at org.apache.tez.runtime.task.TezTaskRunner$TaskRunnerCallable.callInternal(TezTaskRunner.java:171)
    at org.apache.tez.runtime.task.TezTaskRunner$TaskRunnerCallable.callInternal(TezTaskRunner.java:167)
    at org.apache.tez.common.CallableWithNdc.call(CallableWithNdc.java:36)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.tez.dag.api.TezUncheckedException: Expected length: 8417166 actual length: 9223372036854775675
    at org.apache.hadoop.mapred.split.TezGroupedSplit.readFields(TezGroupedSplit.java:128)
    at org.apache.hadoop.io.serializer.WritableSerialization$WritableDeserializer.deserialize(WritableSerialization.java:71)
    at org.apache.hadoop.io.serializer.WritableSerialization$WritableDeserializer.deserialize(WritableSerialization.java:42)
    at org.apache.tez.mapreduce.hadoop.MRInputHelpers.createOldFormatSplitFromUserPayload(MRInputHelpers.java:177)
    at org.apache.tez.mapreduce.lib.MRInputUtils.getOldSplitDetailsFromEvent(MRInputUtils.java:136)
    at org.apache.tez.mapreduce.input.MRInput.initFromEventInternal(MRInput.java:643)
    at org.apache.tez.mapreduce.input.MRInput.initFromEvent(MRInput.java:621)
    at org.apache.tez.mapreduce.input.MRInputLegacy.checkAndAwaitRecordReaderInitialization(MRInputLegacy.java:145)
    at org.apache.tez.mapreduce.input.MRInputLegacy.init(MRInputLegacy.java:109)
    at org.apache.hadoop.hive.ql.exec.tez.MapRecordProcessor.getMRInput(MapRecordProcessor.java:390)
    at org.apache.hadoop.hive.ql.exec.tez.MapRecordProcessor.init(MapRecordProcessor.java:128)
    at org.apache.hadoop.hive.ql.exec.tez.TezProcessor.initializeAndRunProcessor(TezProcessor.java:147)
    ... 14 more

我一点也不明白tez所说的预期长度和实际长度是什么意思。
我们使用hive1.2.1、yarn 2.7.1、hadoop 2.7.1.2.3.2.0-2950