[ https://issues.apache.org/jira/browse/HIVE-7859?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Gopal V updated HIVE-7859: -------------------------- Attachment: HIVE-7859.1.patch > Tune zlib compression in ORC to account for the encoding strategy > ----------------------------------------------------------------- > > Key: HIVE-7859 > URL: https://issues.apache.org/jira/browse/HIVE-7859 > Project: Hive > Issue Type: Bug > Components: File Formats > Reporter: Gopal V > Attachments: HIVE-7859.1.patch > > > Currently ORC Zlib is slow because several compression strategies ZLib uses > is already done by ORC in itself (dictionary, RLE, bit-packing). > We need to pick between Z_FILTERED, Z_HUFFMAN_ONLY, Z_RLE, Z_FIXED and > Z_DEFAULT_STRATEGY according to column stream type. > For instance an RLE_V2 stream could a use Z_FILTERED compression without > invoking the rest of the strategies. > The string streams can use Z_FIXED compression strategies and so on. > The core limitation to stick to retain compatibility with the default > decompressor, so that these are automatically backward compatible. -- This message was sent by Atlassian JIRA (v6.3.4#6332)