File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
http://aspose.com/file-tools
The moose likes Hadoop and the fly likes Hive Gzip Compression splitting supported now? Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login


Win a copy of OCA/OCP Java SE 7 Programmer I & II Study Guide this week in the OCPJP forum!
JavaRanch » Java Forums » Databases » Hadoop
Bookmark "Hive Gzip Compression splitting supported now?" Watch "Hive Gzip Compression splitting supported now?" New topic
Author

Hive Gzip Compression splitting supported now?

Darrel Riekhof
Greenhorn

Joined: May 21, 2009
Posts: 1
Does Hadoop automatically support splitting Gzip files into Blocks now? I have read that splitting doesn't work for tables using gzip compression in Hadoop/Hive here:

https://cwiki.apache.org/Hive/compressedstorage.html

From the above link: "in this case Hadoop will not be able to split your file into chunks/blocks and run multiple maps in parallel. This can cause under-utilization of your cluster's 'mapping' power."

However, when I load my table exactly as they describe, I notice that the gz I load is definately split up into blocks in the place it stores my HDFS files. It looks like this after doing the load:



It is clearly chopping it up into 64 mb blocks during the load to HDFS.

Is this something they have added recently? I'm using Hadoop 1.0.4, r1393290 in psuedo cluster mode.
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: Hive Gzip Compression splitting supported now?