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Konstantin Shvachko commented on HADOOP-894: -------------------------------------------- Summarizing: - LocatedBlocks open(String src); - LocatedBlocks getBlockLocations(String file, long start, long length); - open() always returns first 10 blocks as decided by the name-node. Does that work for everybody? > dfs client protocol should allow asking for parts of the block map > ------------------------------------------------------------------ > > Key: HADOOP-894 > URL: https://issues.apache.org/jira/browse/HADOOP-894 > Project: Hadoop > Issue Type: Improvement > Components: dfs > Reporter: Owen O'Malley > Assigned To: Konstantin Shvachko > Attachments: partialBlockList.patch, partialBlockList2.patch > > > I think that the HDFS client protocol should change like: > /** The meta-data about a file that was opened. */ > class OpenFileInfo { > /** the info for the first block */ > public LocatedBlockInfo getBlockInfo(); > public long getBlockSize(); > public long getLength(); > } > interface ClientProtocol extends VersionedProtocol { > public OpenFileInfo open(String name) throws IOException; > /** get block info for any range of blocks */ > public LocatedBlockInfo[] getBlockInfo(String name, int blockOffset, int > blockLength) throws IOException; > } > so that the client can decide how much block info to request and when. > Currently, when the file is opened or an error occurs, the entire block list > is requested and sent. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.