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Chris Douglas updated HDFS-13186: --------------------------------- Status: Patch Available (was: Open) > [PROVIDED Phase 2] Multipart Multinode uploader API + Implementations > --------------------------------------------------------------------- > > Key: HDFS-13186 > URL: https://issues.apache.org/jira/browse/HDFS-13186 > Project: Hadoop HDFS > Issue Type: Sub-task > Reporter: Ewan Higgs > Assignee: Ewan Higgs > Priority: Major > Attachments: HDFS-13186.001.patch, HDFS-13186.002.patch, > HDFS-13186.003.patch, HDFS-13186.004.patch, HDFS-13186.005.patch, > HDFS-13186.006.patch, HDFS-13186.007.patch, HDFS-13186.008.patch, > HDFS-13186.009.patch > > > To write files in parallel to an external storage system as in HDFS-12090, > there are two approaches: > # Naive approach: use a single datanode per file that copies blocks locally > as it streams data to the external service. This requires a copy for each > block inside the HDFS system and then a copy for the block to be sent to the > external system. > # Better approach: Single point (e.g. Namenode or SPS style external client) > and Datanodes coordinate in a multipart - multinode upload. > This system needs to work with multiple back ends and needs to coordinate > across the network. So we propose an API that resembles the following: > {code:java} > public UploadHandle multipartInit(Path filePath) throws IOException; > public PartHandle multipartPutPart(InputStream inputStream, > int partNumber, UploadHandle uploadId) throws IOException; > public void multipartComplete(Path filePath, > List<Pair<Integer, PartHandle>> handles, > UploadHandle multipartUploadId) throws IOException;{code} > Here, UploadHandle and PartHandle are opaque handlers in the vein of > PathHandle so they can be serialized and deserialized in hadoop-hdfs project > without knowledge of how to deserialize e.g. S3A's version of a UpoadHandle > and PartHandle. > In an object store such as S3A, the implementation is straight forward. In > the case of writing multipart/multinode to HDFS, we can write each block as a > file part. The complete call will perform a concat on the blocks. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org