[ https://issues.apache.org/jira/browse/SPARK-8008?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14567240#comment-14567240 ]
Rene Treffer commented on SPARK-8008: ------------------------------------- I've seen very poor performance when streaming it as one partition for example ("WHERE 1=1"). I'll retry with different partition counts. But I still think there should be a warning about the behavior, as I didn't naturally understand that partition count == parallelism in this case (although it's logical after some thinking). > sqlContext.jdbc can kill your database due to high concurrency > -------------------------------------------------------------- > > Key: SPARK-8008 > URL: https://issues.apache.org/jira/browse/SPARK-8008 > Project: Spark > Issue Type: Bug > Reporter: Rene Treffer > > Spark tries to load as many partitions as possible in parallel, which can in > turn overload the database although it would be possible to load all > partitions given a lower concurrency. > It would be nice to either limit the maximum concurrency or to at least warn > about this behavior. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org