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https://issues.apache.org/jira/browse/HDFS-7587?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14366499#comment-14366499
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Tsz Wo Nicholas Sze commented on HDFS-7587:
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- In verifyQuotaForUCBlock,
-* let's add a precondition check to make sure delta >= 0 (for append).
-* It should check if (!fsd.getFSNamesystem().isImageLoaded() ||
fsd.shouldSkipQuotaChecks()); see FSDirConcatOp.verifyQuota and
FSDirRenameOp.verifyQuotaForRename.
- We should also verity quota by storage types; see
FSDirConcatOp.computeQuotaDeltas.
- For truncate, the quota should be updated differently as following:
-* Copy-on-truncate for snapshot: need quota check for creating the new block.
Quota usage count is increased.
-* Non-copy-on-truncate OR Copy-on-truncate for upgrade but not snapshot: Quota
usage count is decreased. No quota check is needed.
Do you want to fix truncate in a different JIRA?
> Edit log corruption can happen if append fails with a quota violation
> ---------------------------------------------------------------------
>
> Key: HDFS-7587
> URL: https://issues.apache.org/jira/browse/HDFS-7587
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: namenode
> Reporter: Kihwal Lee
> Assignee: Jing Zhao
> Priority: Blocker
> Attachments: HDFS-7587.001.patch, HDFS-7587.002.patch, HDFS-7587.patch
>
>
> We have seen a standby namenode crashing due to edit log corruption. It was
> complaining that {{OP_CLOSE}} cannot be applied because the file is not
> under-construction.
> When a client was trying to append to the file, the remaining space quota was
> very small. This caused a failure in {{prepareFileForWrite()}}, but after the
> inode was already converted for writing and a lease added. Since these were
> not undone when the quota violation was detected, the file was left in
> under-construction with an active lease without edit logging {{OP_ADD}}.
> A subsequent {{append()}} eventually caused a lease recovery after the soft
> limit period. This resulted in {{commitBlockSynchronization()}}, which closed
> the file with {{OP_CLOSE}} being logged. Since there was no corresponding
> {{OP_ADD}}, edit replaying could not apply this.
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