HDFS assumes in hundreds of places that blocks never shrink. So, there is no option to truncate a block.
-Todd On Mon, Jun 21, 2010 at 9:41 PM, Vidur Goyal <vi...@students.iiit.ac.in>wrote: > Hi All, > > In FSNamesystem#startFileInternal , whenever there is a overwrite flag set > , why is the INode removed from the namespace and a new > INodeFileUnderConstruction is created. Why can't we use the convert the > same INode to INodeFileUnderConstruction. And we start writing to the same > blocks at the same datanodes (after incrementing the GS) followed by > either truncating the remaining blocks(if the file size decreases) or > allocating new blocks (if the file size increases). This will decrease > data redundancy and the job of garbage collector and will increase > security. > > vidur > > > > > -- > This message has been scanned for viruses and > dangerous content by MailScanner, and is > believed to be clean. > > -- Todd Lipcon Software Engineer, Cloudera
