[ http://issues.apache.org/jira/browse/HADOOP-764?page=comments#action_12456515 ] Raghu Angadi commented on HADOOP-764: -------------------------------------
Regd references: Say Bx is a block in Namenode.blockMap and Bx_ref is in Dx.blocks as desired. Now when we update Dx.block in processReport(), we do Dx.blocks.clear() : i.e. Bx_ref is removed. Bx_new_ref in newReport array is added to Dx.block. So there are two separate objects referenced by namenode.blockMap and Dx.block. newReport[] does not hold reference to blocks in namenode.blockMap (as far as I can see). What I am missing? > The memory consumption of processReport() in the namenode can be reduced > ------------------------------------------------------------------------ > > Key: HADOOP-764 > URL: http://issues.apache.org/jira/browse/HADOOP-764 > Project: Hadoop > Issue Type: Bug > Components: dfs > Reporter: dhruba borthakur > Assigned To: dhruba borthakur > Attachments: processBlockReport3.patch > > > The FSNamesystem.processReport() method converts the blocklist for a datanode > into an array by calling node.getBlocks(). Although this memory allocation is > transient, it could possibly require the garbage-collector to work that much > harder. > The method Block.getBlocks() should be deprecated. Code that currently uses > this method should instead iterate over the Collection. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
