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https://issues.apache.org/jira/browse/HDFS-16293?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Yuanxin Zhu updated HDFS-16293:
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Description:
When I open the ECN and use Terasort(500G,8 DataNodes,76 vcores/DN) for
testing, DataNodes are congested(HDFS-8008). The client enters the sleep state
after receiving the ACK for many times, but does not release the 'dataQueue'.
The ResponseProcessor thread needs the 'dataQueue' to execute
'ackQueue.getFirst()', so the ResponseProcessor will wait for the client to
release the 'dataQueue', which is equivalent to that the ResponseProcessor
thread also enters sleep, resulting in ACK delay.MapReduce tasks can be delayed
by tens of minutes or even hours.
The DataStreamer thread can first execute 'one = dataQueue. getFirst()',
release 'dataQueue', and then judge whether to execute 'backOffIfNecessary()'
according to 'one.isHeartbeatPacket()'
was:
When I open the ECN and use Terasort for testing, DataNodes are
congested(HDFS-8008). The client enters the sleep state after receiving the ACK
for many times, but does not release the 'dataQueue'. The ResponseProcessor
thread needs the 'dataQueue' to execute 'ackQueue.getFirst()', so the
ResponseProcessor will wait for the client to release the 'dataQueue', which is
equivalent to that the ResponseProcessor thread also enters sleep, resulting in
ACK delay.MapReduce tasks can be delayed by tens of minutes or even hours.
The DataStreamer thread can first execute 'one = dataQueue. getFirst()',
release 'dataQueue', and then judge whether to execute 'backOffIfNecessary()'
according to 'one.isHeartbeatPacket()'
> Client sleeps and holds 'dataQueue' when DataNodes are congested
> ----------------------------------------------------------------
>
> Key: HDFS-16293
> URL: https://issues.apache.org/jira/browse/HDFS-16293
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: hdfs-client
> Affects Versions: 3.2.2
> Reporter: Yuanxin Zhu
> Priority: Major
> Original Estimate: 24h
> Remaining Estimate: 24h
>
> When I open the ECN and use Terasort(500G,8 DataNodes,76 vcores/DN) for
> testing, DataNodes are congested(HDFS-8008). The client enters the sleep
> state after receiving the ACK for many times, but does not release the
> 'dataQueue'. The ResponseProcessor thread needs the 'dataQueue' to execute
> 'ackQueue.getFirst()', so the ResponseProcessor will wait for the client to
> release the 'dataQueue', which is equivalent to that the ResponseProcessor
> thread also enters sleep, resulting in ACK delay.MapReduce tasks can be
> delayed by tens of minutes or even hours.
> The DataStreamer thread can first execute 'one = dataQueue. getFirst()',
> release 'dataQueue', and then judge whether to execute 'backOffIfNecessary()'
> according to 'one.isHeartbeatPacket()'
>
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