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ASF GitHub Bot commented on HDFS-16845: --------------------------------------- simbadzina opened a new pull request, #5142: URL: https://github.com/apache/hadoop/pull/5142 HDFS-16845: Adds configuration flag to allow clients to use router observer reads without using the ObserverReadProxyProvider. <!-- Thanks for sending a pull request! 1. If this is your first time, please read our contributor guidelines: https://cwiki.apache.org/confluence/display/HADOOP/How+To+Contribute 2. Make sure your PR title starts with JIRA issue id, e.g., 'HADOOP-17799. Your PR title ...'. --> ### Description of PR Description In order for clients to have routers forward their reads to observers, the clients must use a proxy with an alignment context. This is currently achieved by using the ObserverReadProxyProvider. Using ObserverReadProxyProvider allows backward compatible for client configurations. However, the ObserverReadProxyProvider forces an msync on initialization which is not required with routers. Performing msync calls is more expensive with routers because the router fans out the cal to all namespace, so we'd like to avoid this. ### How was this patch tested? New test cases in TestObserverWithRouter. ### For code changes: - [ x] Does the title or this PR starts with the corresponding JIRA issue id (e.g. 'HADOOP-17799. Your PR title ...')? > Add configuration flag to enable observer reads on routers without using > ObserverReadProxyProvider > -------------------------------------------------------------------------------------------------- > > Key: HDFS-16845 > URL: https://issues.apache.org/jira/browse/HDFS-16845 > Project: Hadoop HDFS > Issue Type: Bug > Reporter: Simbarashe Dzinamarira > Assignee: Simbarashe Dzinamarira > Priority: Major > > In order for clients to have routers forward their reads to observers, the > clients must use a proxy with an alignment context. This is currently > achieved by using the ObserverReadProxyProvider. > Using ObserverReadProxyProvider allows backward compatible for client > configurations. > However, the ObserverReadProxyProvider forces an msync on initialization > which is not required with routers. > Performing msync calls is more expensive with routers because the router fans > out the cal to all namespace, so we'd like to avoid this. -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org