hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Mukul Kumar Singh (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HDFS-11921) Ozone: KSM: Unable to put keys with zero length
Date Tue, 12 Sep 2017 16:04:00 GMT

    [ https://issues.apache.org/jira/browse/HDFS-11921?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16163163#comment-16163163
] 

Mukul Kumar Singh commented on HDFS-11921:
------------------------------------------

This is needed for OzoneFileSystem as well, where this API is needed for directories. Directories
will have keys with no data.

> Ozone: KSM: Unable to put keys with zero length
> -----------------------------------------------
>
>                 Key: HDFS-11921
>                 URL: https://issues.apache.org/jira/browse/HDFS-11921
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>          Components: ozone
>    Affects Versions: HDFS-7240
>            Reporter: Anu Engineer
>            Priority: Minor
>              Labels: OzonePostMerge
>         Attachments: HDFS-11921-HDFS-7240.001.patch
>
>
> As part of working on HDFS-11909, I was trying to put zero length keys. I found that
put key refuses to do that. Here is the call trace, 
> bq.	at ScmBlockLocationProtocolClientSideTranslatorPB.allocateBlock 
> we check if the block size is greater than 0, which makes sense since we should not call
into SCM to allocate a block of zero size.
> However these 2 calls are invoked for creating the key, so that metadata for key can
be created, we should probably take care of this behavior here.
> bq. ksm.KeyManagerImpl.allocateKey
> bq. ksm.KeySpaceManager.allocateKey(KeySpaceManager.java:428)
> Another way to fix this might be to just allocate a block with at least 1 byte always,
which might be easier than special casing code.
> [~vagarychen] Would you like to fix this in the next patch you are working on ? 



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-help@hadoop.apache.org


Mime
View raw message