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HBase >> mail # user >> Hbase import Tsv performance (slow import)

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Re: Hbase import Tsv performance (slow import)
As Kevin suggested we can make use of bulk load that goes thro WAL and
Memstore.  Or the second option will be to use the o/p of mappers to create
HFiles directly.


On Wed, Oct 24, 2012 at 8:59 AM, Anoop John <[EMAIL PROTECTED]> wrote:

> Hi
>     Using ImportTSV tool you are trying to bulk load your data. Can you see
> and tell how many mappers and reducers were there. Out of total time what
> is the time taken by the mapper phase and by the reducer phase.  Seems like
> MR related issue (may be some conf issue). In this bulk load case most of
> the work is done by the MR job. It will read the raw data and convert it
> into Puts and write to HFiles. MR o/p is HFiles itself. The next part in
> ImportTSV will just put the HFiles under the table region store..  There
> wont be WAL usage in this bulk load.
> -Anoop-
> On Tue, Oct 23, 2012 at 9:18 PM, Nick maillard <
> > Hi everyone
> >
> > I'm starting with hbase and testing for our needs. I have set up a hadoop
> > cluster of Three machines and A Hbase cluster atop on the same three
> > machines,
> > one master two slaves.
> >
> > I am testing the Import of a 5GB csv file with the importTsv tool. I
> > import the
> > file in the HDFS and use the importTsv tool to import in Hbase.
> >
> > Right now it takes a little over an hour to complete. It creates around 2
> > million entries in one table with a single family.
> > If I use bulk uploading it goes down to 20 minutes.
> >
> > My hadoop has 21 map tasks but they all seem to be taking a very long
> time
> > to
> > finish many tasks end up in time out.
> >
> > I am wondering what I have missed in my configuration. I have followed
> the
> > different prerequisites in the documentations but I am really unsure as
> to
> > what
> > is causing this slow down. If I were to apply the wordcount example to
> the
> > same
> > file it takes only minutes to complete so I am guessing the issue lies in
> > my
> > Hbase configuration.
> >
> > Any help or pointers would by appreciated
> >
> >