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https://issues.apache.org/jira/browse/HDFS-13689?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17802444#comment-17802444
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Shilun Fan edited comment on HDFS-13689 at 1/4/24 7:56 AM:
-----------------------------------------------------------
Bulk update: moved all 3.4.0 non-blocker issues, please move back if it is a
blocker. Retarget 3.5.0.
was (Author: slfan1989):
updated the target version for preparing 3.4.0 release.
> NameNodeRpcServer getEditsFromTxid assumes it is run on active NameNode
> -----------------------------------------------------------------------
>
> Key: HDFS-13689
> URL: https://issues.apache.org/jira/browse/HDFS-13689
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Components: hdfs, namenode
> Reporter: Erik Krogen
> Priority: Major
>
> {{NameNodeRpcServer#getEditsFromTxid}} currently decides which transactions
> are able to be served, i.e. which transactions are durable, using the
> following logic:
> {code}
> long syncTxid = log.getSyncTxId();
> // If we haven't synced anything yet, we can only read finalized
> // segments since we can't reliably determine which txns in in-progress
> // segments have actually been committed (e.g. written to a quorum of
> JNs).
> // If we have synced txns, we can definitely read up to syncTxid since
> // syncTxid is only updated after a transaction is committed to all
> // journals. (In-progress segments written by old writers are already
> // discarded for us, so if we read any in-progress segments they are
> // guaranteed to have been written by this NameNode.)
> boolean readInProgress = syncTxid > 0;
> {code}
> This assumes that the NameNode serving this request is the current
> writer/active NameNode, which may not be true in the ObserverNode situation.
> Since {{selectInputStreams}} now has a {{onlyDurableTxns}} flag, which, if
> enabled, will only return durable/committed transactions, we can instead
> leverage this to provide the same functionality. We should utilize this to
> avoid consistency issues when serving this request from the ObserverNode.
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