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Sriranjan Manjunath updated PIG-872: ------------------------------------ Attachment: (was: PIG_872.patch) > use distributed cache for the replicated data set in FR join > ------------------------------------------------------------ > > Key: PIG-872 > URL: https://issues.apache.org/jira/browse/PIG-872 > Project: Pig > Issue Type: Improvement > Reporter: Olga Natkovich > Assignee: Sriranjan Manjunath > > Currently, the replicated file is read directly from DFS by all maps. If the > number of the concurrent maps is huge, we can overwhelm the NameNode with > open calls. > Using distributed cache will address the issue and might also give a > performance boost since the file will be copied locally once and the reused > by all tasks running on the same machine. > The basic approach would be to use cacheArchive to place the file into the > cache on the frontend and on the backend, the tasks would need to refer to > the data using path from the cache. > Note that cacheArchive does not work in Hadoop local mode. (Not a problem for > us right now as we don't use it.) -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.