[ http://issues.apache.org/jira/browse/HADOOP-474?page=comments#action_12430590 ] Doug Cutting commented on HADOOP-474: -------------------------------------
+1, with a few questions: Do we need io.compression.codecs if the codecs provide extensions? If so, then what's the point of having the codec's provide extensions? Should the output property be instead named mapred.text.output.compression.codec? In other words, will we use this same property to name the codecs for other output formats, or is this property for text files alone (in which case it should have 'text' in its name)? > support compressed text files as input and output > ------------------------------------------------- > > Key: HADOOP-474 > URL: http://issues.apache.org/jira/browse/HADOOP-474 > Project: Hadoop > Issue Type: Improvement > Components: mapred > Affects Versions: 0.5.0 > Reporter: Owen O'Malley > Assigned To: Owen O'Malley > Fix For: 0.6.0 > > > I'd like TextInputFomat and TextOutputFormat to automatically compress and > uncompress text files when they are read and written. Furthermore, I'd like > to be able to use custom compressors as defined in HADOOP-441. Therefore, I > propose: > Adding a map of compression codecs in the server config files: > io.compression.codecs = "<suffix>=<codec class>,..." > so the default would be something like: > <property> > <name>io.compression.codecs</name> > > <value>.gz=org.apache.hadoop.io.GZipCodec,.Z=org.apache.hadoop.io.ZipCodec</value> > <description>A list of file suffixes and the codecs for them.</description> > </property> > note that the suffix can include multiple "." so you could support suffixes > like ".tar.gz", but they are just treated as literals against the end of the > filename. > If the TextInputFormat is dealing with such a file, it: > 1. makes a single split > 2. decompresses automatically > On the output side, if mapred.output.compress is true, then TextOutputFormat > would use a new property mapred.output.compression.codec that would define > the codec to use to compress the outputs, defaulting to gzip. -- 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
