使用 MLCP 复制数据时解析 HTTP headers 异常时出错

Question

我正在尝试使用 MLCP 将大量数据从一个数据库复制到另一个数据库，但出现以下异常。

2019-08-30 11:53:54.847 SEVERE [15] (StreamingResultSequence.next): IOException instantiating ResultItem 130891: Error parsing HTTP headers: Premature EOF, partial header line read: 'X-URI: /integration/test%2BItem%2BBarcode%2BCross%2BR'
 java.io.IOException: Error parsing HTTP headers: Premature EOF, partial header line read: 'X-URI: /integration/test%2BItem%2BBarcode%2BCross%2BR'
        com.marklogic.http.HttpHeaders.parsePlainHeaders(HttpHeaders.java:317)
        com.marklogic.http.MultipartBuffer.next(MultipartBuffer.java:103)
        com.marklogic.xcc.impl.AbstractResultSequence.instantiateResultItem(AbstractResultSequence.java:132)
        com.marklogic.xcc.impl.StreamingResultSequence.next(StreamingResultSequence.java:147)
        com.marklogic.xcc.impl.StreamingResultSequence.next(StreamingResultSequence.java:166)
        com.marklogic.contentpump.DatabaseContentReader.nextKeyValue(DatabaseContentReader.java:518)
        com.marklogic.contentpump.LocalJobRunner$TrackingRecordReader.nextKeyValue(LocalJobRunner.java:498)
        org.apache.hadoop.mapreduce.task.MapContextImpl.nextKeyValue(MapContextImpl.java:80)
        org.apache.hadoop.mapreduce.lib.map.WrappedMapper$Context.nextKeyValue(WrappedMapper.java:91)
        com.marklogic.contentpump.BaseMapper.run(BaseMapper.java:78)
        com.marklogic.contentpump.LocalJobRunner$LocalMapTask.call(LocalJobRunner.java:411)
        java.util.concurrent.FutureTask.run(Unknown Source)
        java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        java.lang.Thread.run(Unknown Source)

请帮助我理解并解决问题。

我正在使用的MLCP命令-

mlcp copy -mode local -input_host 192.168.1.46 -input_port 9000 -input_username admin -input_password admin -input_database test  -output_host localhost -output_port 8000 -output_username admin -output_password admin -output_database test

Answer 1

听起来您可能遇到了一些超时情况。有一篇 MarkLogic 知识库文章描述了可能发生这种情况的常见情况以及一些有助于避免这些情况的方法。

https://help.marklogic.com/Knowledgebase/Article/View/75/0/explaining-and-preventing-premature-eof-errors-when-loading-content-via-xcc

The premature EOF exception generally occurs in situations where a connection to a particular application server connection was lost while the XCC driver was in the process of reading a result set. This can happen in a few possible scenarios:

The host became unavailable due to a hardware issue, segfault or similar issue;

The query timeout expired (although this is much more likely to yield an XDMP-EXTIME exception with a "Time limit exceeded" message);

Network interruption - a possible indicator of a network reliability problem such as a misconfigured load balancer or a fault in some other network hardware.

配置/代码：第一次看到此消息时要尝试的操作

A possible cause of errors like this may be due to the JVM starting garbage collection and this process taking long enough as to exceed the server timeout setting. If this is the case, try adding the -XX:+UseConcMarkSweepGC java option

Setting the "keep-alive" value to zero for the affected XDBC application server will disable socket pooling and may help to prevent this condition from arising; with keep-alive set to zero, sockets will not be re-used. With this approach, it is understood that disabling keep-alive should not be expected to have a significant negative impact on performance, although thorough testing is nevertheless advised.

使用 MLCP 复制数据时解析 HTTP headers 异常时出错

Error parsing HTTP headers exception while copying data using MLCP

marklogic

mlcp

配置/代码：第一次看到此消息时要尝试的操作