[ 
https://issues.apache.org/jira/browse/HDFS-13779?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16597855#comment-16597855
 ] 

Konstantin Shvachko commented on HDFS-13779:
--------------------------------------------

Looks good, Erik. Two comments from me:
# In ORPP you use raw types: "References to generic type 
AbstractNNFailoverProxyProvider<T> should be parameterized"
# Unused imports (2) in {{TestObserverReadProxyProvider}}.
# For {{CachingHAProxyFactory}} I don't think we achieve much here. It still 
stores the the Proxy twice - one in the {{backingFactory}} and another in the 
cache. If want to cache proxies we should do it in the RPC engine globally for 
all proxies. I suggest we skip this optimization for now.
# Also {{TestObserverNode}} fails for me with your patch. I can debug if it is 
only on my box.

> Implement performFailover logic for ObserverReadProxyProvider.
> --------------------------------------------------------------
>
>                 Key: HDFS-13779
>                 URL: https://issues.apache.org/jira/browse/HDFS-13779
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>          Components: hdfs-client
>            Reporter: Konstantin Shvachko
>            Assignee: Erik Krogen
>            Priority: Major
>         Attachments: HDFS-13779-HDFS-12943.000.patch, 
> HDFS-13779-HDFS-12943.001.patch, HDFS-13779-HDFS-12943.WIP00.patch
>
>
> Currently {{ObserverReadProxyProvider}} inherits {{performFailover()}} method 
> from {{ConfiguredFailoverProxyProvider}}, which simply increments the index 
> and switches over to another NameNode. The logic for ORPP should be smart 
> enough to choose another observer, otherwise it can switch to a SBN, where 
> reads are disallowed, or to an ANN, which defeats the purpose of reads from 
> standby.
> This was discussed in HDFS-12976.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

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

Reply via email to