When it is set to true (default), DN uses JDK's transferTo() interface to avoid extra buffer copies.
It is possible though rare, some specific platform may not support this efficiently or is unstable. The config exists to let users disable this optimization. We have not seen any users that have disabled this though... Raghu. On Sun, Nov 14, 2010 at 9:56 AM, Thanh Do <than...@cs.wisc.edu> wrote: > got it here > https://issues.apache.org/jira/browse/HADOOP-3164 > > > On Sun, Nov 14, 2010 at 11:31 AM, Thanh Do <than...@cs.wisc.edu> wrote: > >> Hi all, >> >> Can somebody let me know what is this >> parameter used for: >> >> dfs.datanode.transferTo.allowed >> >> It is not in default config, >> and the maxChunksPerPacket depends on it. >> >> Thanks so much. >> Thanh >> > >
