Mailing-List: contact user-help@hbase.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@hbase.apache.org
Received-SPF: pass (athena.apache.org: domain of saint.ack@gmail.com
 designates 209.85.220.169 as permitted sender)
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=mime-version:sender:in-reply-to:references:date
         :x-google-sender-auth:message-id:subject:from:to:cc:content-type;
        b=qx+SST5j5Id1wL5bhoGbXW3jNJOVmsX2Nj4uFnVjAAkFOrQN4H46MsxX7Lg66Qg94b
         6HOiDqa/paj96Ig1MvWY9MNGvNLnObXXT6g9GwonzBKu0jYstxWuNhEYDdMRpUCDjhIQ
         h39K4GkhMDWMYGAl1prjQu3t185RXg+Zn+ceY=
MIME-Version: 1.0
Sender: saint.ack@gmail.com
In-Reply-To: <AANLkTimcrikrj=hD6BBkO5352pEqKK=BgHHHk===Nci1@mail.gmail.com>
References: <AANLkTimcrikrj=hD6BBkO5352pEqKK=BgHHHk===Nci1@mail.gmail.com>
Date: Fri, 25 Mar 2011 11:19:10 -0700
Message-ID: <AANLkTi=CXoFz8VqmNKVW8FiOyJohVMPrVm_Aihz0pnws@mail.gmail.com>
Subject: Re: How could I re-calculate every entries in hbase efficiently
 through mapreduce?
From: Stack <stack@duboce.net>
To: user@hbase.apache.org
Cc: Stanley Xu <wenhao.xu@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

On Thu, Mar 24, 2011 at 7:36 PM, Stanley Xu <wenhao.xu@gmail.com> wrote:
> But I have two doubts here:
> 1. It looks the partitioner will do a lots of shuffling, I am wondering why
> it couldn't just do the put on the local region since the read and write on
> the same entry should be on the same region, isn't it?
>

There is a little on this in the mapreduce package javadoc:
http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/mapreduce/package-summary.html#sink


> 2. If the job failed for any reason(like timeout), the HBase might be in a
> partial-updated status, is it?
>

This is a problem you'll have to figure.  Turn of speculative execution for one.

St.Ack