[
https://issues.apache.org/jira/browse/HDFS-7990?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Daryn Sharp updated HDFS-7990:
------------------------------
Status: Patch Available (was: Open)
> IBR delete ack should not be delayed
> ------------------------------------
>
> Key: HDFS-7990
> URL: https://issues.apache.org/jira/browse/HDFS-7990
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: namenode
> Affects Versions: 2.0.0-alpha
> Reporter: Daryn Sharp
> Assignee: Daryn Sharp
> Attachments: HDFS-7990.patch
>
>
> HDFS-395 added the incremental BR feature. A concern was avoiding a race
> condition with ack-ing block invalidates followed by the directory scanner
> re-adding the block before the async delete service removes the block,
> possibly resulting in a full BR that includes the previously delete ack-ed
> block.
> The solution was to batch & delay block deletion acks via a hardcoded
> interval of 100 * heartbeat interval (default: 5min). The delay isn't
> required:
> # The {{FSDatasetSpi}} tracks blocks pending deletions precisely so the
> scanner won't re-add the block to the volume map
> # Block receiving, received, and deleted go into the same pending report. A
> block received event will trigger an immediate IBR which includes the
> deletion acks. Ie. The delay is meaningless for all but a quiescent cluster
> # Failing to promptly report deleted blocks on a quiescent cluster prevents
> the NN from updating the block maps to remove the locations
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
