I may be nitpicking here but if "perhaps the answer is no" then I conclude: Perhaps the other implementations of RecordWriter are a race condition/file corruption ready to occur.
On Thu, Aug 8, 2013 at 12:50 PM, Harsh J <[email protected]> wrote: > 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 >>>>> >>>> >>> -- Best regards / Met vriendelijke groeten, Niels Basjes
