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Andrew Wang commented on HDFS-10301: ------------------------------------ My understanding of PB is that we have a fixed 4 bits for tags, so there isn't really overhead to adding more PB fields as long as they are optional or repeated. See: https://developers.google.com/protocol-buffers/docs/encoding Given that, I'd err on the side of readability rather than trying to reuse existing fields. Since block reports are a pretty infrequent operation, I wouldn't stress over a few bytes if we end up filling a required field with a dummy value. I agree with Colin that the current overloading of BlockListAsLongs is confusing. > BlockReport retransmissions may lead to storages falsely being declared > zombie if storage report processing happens out of order > -------------------------------------------------------------------------------------------------------------------------------- > > Key: HDFS-10301 > URL: https://issues.apache.org/jira/browse/HDFS-10301 > Project: Hadoop HDFS > Issue Type: Bug > Components: namenode > Affects Versions: 2.6.1 > Reporter: Konstantin Shvachko > Assignee: Vinitha Reddy Gankidi > Priority: Critical > Attachments: HDFS-10301.002.patch, HDFS-10301.003.patch, > HDFS-10301.004.patch, HDFS-10301.005.patch, HDFS-10301.006.patch, > HDFS-10301.007.patch, HDFS-10301.008.patch, HDFS-10301.009.patch, > HDFS-10301.01.patch, HDFS-10301.010.patch, HDFS-10301.011.patch, > HDFS-10301.sample.patch, zombieStorageLogs.rtf > > > When NameNode is busy a DataNode can timeout sending a block report. Then it > sends the block report again. Then NameNode while process these two reports > at the same time can interleave processing storages from different reports. > This screws up the blockReportId field, which makes NameNode think that some > storages are zombie. Replicas from zombie storages are immediately removed, > causing missing blocks. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org