Return-Path: X-Original-To: apmail-hadoop-mapreduce-user-archive@minotaur.apache.org Delivered-To: apmail-hadoop-mapreduce-user-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id EE01310B4A for ; Tue, 21 Jan 2014 10:37:15 +0000 (UTC) Received: (qmail 99836 invoked by uid 500); 21 Jan 2014 10:37:06 -0000 Delivered-To: apmail-hadoop-mapreduce-user-archive@hadoop.apache.org Received: (qmail 98949 invoked by uid 500); 21 Jan 2014 10:37:03 -0000 Mailing-List: contact user-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@hadoop.apache.org Delivered-To: mailing list user@hadoop.apache.org Received: (qmail 98913 invoked by uid 99); 21 Jan 2014 10:37:01 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 21 Jan 2014 10:37:01 +0000 X-ASF-Spam-Status: No, hits=-0.7 required=5.0 tests=RCVD_IN_DNSWL_LOW,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of lukas.xtreemfs@googlemail.com designates 209.85.214.45 as permitted sender) Received: from [209.85.214.45] (HELO mail-bk0-f45.google.com) (209.85.214.45) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 21 Jan 2014 10:36:55 +0000 Received: by mail-bk0-f45.google.com with SMTP id v16so2901430bkz.18 for ; Tue, 21 Jan 2014 02:36:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject :content-type:content-transfer-encoding; bh=us9q1XXON+AbL7h5iAQgNRgT5ZyhAQyHwokj+T8rcUM=; b=w4bN8lsJYySVKE48HstQR3Cb9J7zcjclG9Rjc8XvuvMVa/IW9wdAWAniR9iFj9u/zi XJ2ZDfAtqzLvffcDNETpzUsBQjpggO9NDlO4hQNOulrl0n9ydSzep4iV/so8KCoET+dt 8Q5E+002mgmqNBW1qePqf+f+IwdN0YEcSKYRaBWAqY0WxZZs8rOv2jOlvK6LEcD7uHOY 2IYC4xEoDPge+Aq+dmm9OJMqMfcNvU0Yv5v7opqtcpNNrDaf8p8DnK0Q8II9cFcyYEUZ iX9cfczKOTwp95sCG+HtAAKTMyTLulJLdFQK39A0QAa2cGm9PxKt16PilfpYkXL6CTXL mYxQ== X-Received: by 10.204.26.69 with SMTP id d5mr743390bkc.47.1390300595519; Tue, 21 Jan 2014 02:36:35 -0800 (PST) Received: from ?IPv6:2a02:810a:c0:e6c:d45f:1b3e:db15:dbde? ([2a02:810a:c0:e6c:d45f:1b3e:db15:dbde]) by mx.google.com with ESMTPSA id dg4sm3551459bkc.10.2014.01.21.02.36.34 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 21 Jan 2014 02:36:35 -0800 (PST) Message-ID: <52DE4DB2.5000008@gmail.com> Date: Tue, 21 Jan 2014 11:36:34 +0100 From: Lukas Kairies User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: user@hadoop.apache.org Subject: Shutdown hook for FileSystems Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Checked: Checked by ClamAV on apache.org Hey, I use Hadoop with XtreemFS (with a corresponding FileSystem implementation). The XtreemFS client uses several non-deamon Threads eg. for communication. Therefore the shutdown hooks do not start after a mapper/reducer is finished and the Child processes do not terminate. My question: Is there any way to determine if the mapper/reducer child processes do not need the file system any more? Best regards, Lukas K