[
https://issues.apache.org/jira/browse/HDFS-13688?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16562713#comment-16562713
]
Chen Liang commented on HDFS-13688:
-----------------------------------
Thanks for the review [~xkrogen]! Posted v005 patch to remove remaining server
side changes.
As for {{getCorrectLastAppliedOrWrittenTxId()}}, I did considered using this
synchronized version. But I was more concerned with the locking overhead than
returning a potentially not the most recent value. Because every single read
call will be grabbing the lock. Also the current {{GlobalStateIdContext}} is
using {{getLastWrittenTransactionId}}, which is also underlying using a
"un-locked" version of written txid.
> Introduce msync API call
> ------------------------
>
> Key: HDFS-13688
> URL: https://issues.apache.org/jira/browse/HDFS-13688
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Reporter: Chen Liang
> Assignee: Chen Liang
> Priority: Major
> Attachments: HDFS-13688-HDFS-12943.001.patch,
> HDFS-13688-HDFS-12943.002.patch, HDFS-13688-HDFS-12943.002.patch,
> HDFS-13688-HDFS-12943.003.patch, HDFS-13688-HDFS-12943.004.patch,
> HDFS-13688-HDFS-12943.005.patch, HDFS-13688-HDFS-12943.WIP.002.patch,
> HDFS-13688-HDFS-12943.WIP.patch
>
>
> As mentioned in the design doc in HDFS-12943, to ensure consistent read, we
> need to introduce an RPC call {{msync}}. Specifically, client can issue a
> msync call to Observer node along with a transactionID. The msync will only
> return when the Observer's transactionID has caught up to the given ID. This
> JIRA is to add this API.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
