While we don't fork by default, we do provide a MultithreadedMapper implementation that would require such synchronization. But if you are asking is it necessary, then perhaps the answer is no. On Aug 8, 2013 3:43 PM, "Azuryy Yu" <[email protected]> wrote:
> its not hadoop forked threads, we may create a line record writer, then > call this writer concurrently. > On Aug 8, 2013 4:00 PM, "Sathwik B P" <[email protected]> wrote: > >> Hi, >> Thanks for your reply. >> May I know where does hadoop fork multiple threads to use a single >> RecordWriter. >> >> regards, >> sathwik >> >> On Thu, Aug 8, 2013 at 7:06 AM, Azuryy Yu <[email protected]> wrote: >> >>> because we may use multi-threads to write a single file. >>> On Aug 8, 2013 2:54 PM, "Sathwik B P" <[email protected]> wrote: >>> >>>> Hi, >>>> >>>> LineRecordWriter.write(..) is synchronized. I did not find any other >>>> RecordWriter implementations define the write as synchronized. >>>> Any specific reason for this. >>>> >>>> regards, >>>> sathwik >>>> >>> >>
