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sam rash commented on HDFS-1057: -------------------------------- hey todd, regarding the 0.20 patch, i was planning on leaving it as-is and working on the patch for trunk. that one will be up to snuff and have all the headers and hopefully be cleaner. otherwise, I'll have 3 concurrent branches to keep going (internal 0.20, 0.20 'refined', and trunk) does that work for you? or do you need a cleaned up 0.20 version for something in particular? > Concurrent readers hit ChecksumExceptions if following a writer to very end > of file > ----------------------------------------------------------------------------------- > > Key: HDFS-1057 > URL: https://issues.apache.org/jira/browse/HDFS-1057 > Project: Hadoop HDFS > Issue Type: Sub-task > Components: data-node > Affects Versions: 0.21.0, 0.22.0 > Reporter: Todd Lipcon > Assignee: sam rash > Priority: Blocker > Attachments: conurrent-reader-patch-1.txt, > conurrent-reader-patch-2.txt, conurrent-reader-patch-3.txt > > > In BlockReceiver.receivePacket, it calls replicaInfo.setBytesOnDisk before > calling flush(). Therefore, if there is a concurrent reader, it's possible to > race here - the reader will see the new length while those bytes are still in > the buffers of BlockReceiver. Thus the client will potentially see checksum > errors or EOFs. Additionally, the last checksum chunk of the file is made > accessible to readers even though it is not stable. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.