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From Thanh Do <than...@cs.wisc.edu>
Subject Re: Why dataOut is FileOutputStream?
Date Sat, 06 Nov 2010 15:15:53 GMT
Thanks Eli,

I got it now.

On Fri, Nov 5, 2010 at 10:36 PM, Eli Collins <eli@cloudera.com> wrote:

> Hey Thanh,
>
> Data gets written in 64KB packets so there doesn't seem to be a need
> to buffer it.
>
> Thanks,
> Eli
>
> On Thu, Nov 4, 2010 at 2:58 PM, Thanh Do <thanhdo@cs.wisc.edu> wrote:
> > Hi all,
> >
> > When a datanode receive a block, the datanode
> > write the block into 2 streams on disk:
> > - the data stream (dataOut)
> > - the checksum stream (checksumOut)
> >
> > While the checksumOut is created with following code:
> >   this.checksumOut = new DataOutputStream(new BufferedOutputStream(
> >                                          streams.checksumOut,
> >                                          SMALL_BUFFER_SIZE));
> > The dataOut is simply FileOutputStream()
> >
> > So, the checksumOut is buffered, but dataOut is not.
> >
> > Is there any particular reason for doing so?
> > or it doesn't matter, because after that, we flush
> > the two streams anyway?
> >
> > Thanks
> > Thanh
> >
>

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