Return-Path: 
 <user-return-4770-apmail-hadoop-common-user-archive=hadoop.apache.org@hadoop.apache.org>
X-Original-To: apmail-hadoop-common-user-archive@www.apache.org
Delivered-To: apmail-hadoop-common-user-archive@www.apache.org
Received: from mail.apache.org (hermes.apache.org [140.211.11.3])
	by minotaur.apache.org (Postfix) with SMTP id 09482EC3A
	for <apmail-hadoop-common-user-archive@www.apache.org>;
 Fri,  1 Feb 2013 03:16:28 +0000 (UTC)
Received: (qmail 85624 invoked by uid 500); 1 Feb 2013 03:16:22 -0000
Delivered-To: apmail-hadoop-common-user-archive@hadoop.apache.org
Received: (qmail 85199 invoked by uid 500); 1 Feb 2013 03:16:21 -0000
Mailing-List: contact user-help@hadoop.apache.org; run by ezmlm
Precedence: bulk
List-Help: <mailto:user-help@hadoop.apache.org>
List-Unsubscribe: <mailto:user-unsubscribe@hadoop.apache.org>
List-Post: <mailto:user@hadoop.apache.org>
List-Id: <user.hadoop.apache.org>
Reply-To: user@hadoop.apache.org
Delivered-To: mailing list user@hadoop.apache.org
Received: (qmail 85170 invoked by uid 99); 1 Feb 2013 03:16:20 -0000
Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230)
    by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 01 Feb 2013 03:16:20 +0000
X-ASF-Spam-Status: No, hits=1.5 required=5.0
	tests=HTML_MESSAGE,RCVD_IN_DNSWL_LOW,SPF_PASS
X-Spam-Check-By: apache.org
Received-SPF: pass (nike.apache.org: domain of cutefish.yx@gmail.com
 designates 209.85.128.169 as permitted sender)
Received: from [209.85.128.169] (HELO mail-ve0-f169.google.com)
 (209.85.128.169)
    by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 01 Feb 2013 03:16:12 +0000
Received: by mail-ve0-f169.google.com with SMTP id 15so815141vea.14
        for <user@hadoop.apache.org>; Thu, 31 Jan 2013 19:15:52 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=gmail.com; s=20120113;
        h=x-received:mime-version:from:date:message-id:subject:to
         :content-type;
        bh=AA6F8wiDbsWnNqa++hWpyRL/uCZt6CzxrynAv16ftJE=;
        b=Q2qUHHnf6DqoLWWdpN0dPGYUYF+P9HoZ95qkRitESU0JuCrlXg19MobmY1J9P54TXz
         JhtOcPHNZaQNm+0jN4Mwcbw0tUYjllx6zM8Khq7tmU7LJJSEfYdvHzW5DoE2wNexJ8n1
         PKLxXD/9s2GpYPI29ENtJKOQX+e3oPiKXGLnh23YT7T7qcXkrDVPGmEn/bbcQPV7P1KS
         dxFuO9mHyDhFewdh3wHf/1NXDc8BCQ/WRLCeWn/hpeX4okzzgmmeLxgQMfsatW8Mm03r
         TnBD+LkVeODq1fq4aqKuvu+RZxvRDA/5XIpwYHnBMPp0sKHvdbSX9N3jkvkdQuGUeWCA
         JfRQ==
X-Received: by 10.52.155.205 with SMTP id vy13mr8999387vdb.119.1359688551927;
 Thu, 31 Jan 2013 19:15:51 -0800 (PST)
MIME-Version: 1.0
Received: by 10.52.88.70 with HTTP; Thu, 31 Jan 2013 19:15:10 -0800 (PST)
From: Xiao Yu <cutefish.yx@gmail.com>
Date: Thu, 31 Jan 2013 22:15:10 -0500
Message-ID: 
 <CAPyYzD4pSQA5ReN0WTG-kTNcEGvZ3ATYd1TPn1WU6s8osqYDnQ@mail.gmail.com>
Subject: What happens when a block is being invalidated/deleted on the
 DataNode when it is being read?
To: user@hadoop.apache.org
Content-Type: multipart/alternative; boundary=bcaec53aecce248df904d4a129ec
X-Virus-Checked: Checked by ClamAV on apache.org

--bcaec53aecce248df904d4a129ec
Content-Type: text/plain; charset=ISO-8859-1

Hi, all

I am wondering if this situation could happen: a block is being
invalidated/deleted on a DataNode(by the NameNode, for example, to delete a
over-replicated block) while it is also concurrently being read (by some
clients). If this could happen, how does hdfs handle this issue?

Thank you very much.

Xiao Yu

--bcaec53aecce248df904d4a129ec
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div style>Hi, all</div><div style><br></div><div style>I =
am wondering if this situation could happen: a block is being invalidated/d=
eleted on a DataNode(by the NameNode, for example, to delete a over-replica=
ted block) while it is also concurrently being read (by some clients). If t=
his could happen, how does hdfs handle this issue?=A0</div>

<div style><br></div><div style>Thank you very much.</div><div><br></div><d=
iv>Xiao Yu</div>
</div>

--bcaec53aecce248df904d4a129ec--