Return-Path: Delivered-To: apmail-hadoop-mapreduce-user-archive@minotaur.apache.org Received: (qmail 65531 invoked from network); 4 Dec 2010 03:05:25 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 4 Dec 2010 03:05:25 -0000 Received: (qmail 45698 invoked by uid 500); 4 Dec 2010 03:05:24 -0000 Delivered-To: apmail-hadoop-mapreduce-user-archive@hadoop.apache.org Received: (qmail 45509 invoked by uid 500); 4 Dec 2010 03:05:24 -0000 Mailing-List: contact mapreduce-user-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: mapreduce-user@hadoop.apache.org Delivered-To: mailing list mapreduce-user@hadoop.apache.org Received: (qmail 45501 invoked by uid 99); 4 Dec 2010 03:05:23 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 04 Dec 2010 03:05:23 +0000 X-ASF-Spam-Status: No, hits=-0.7 required=10.0 tests=FREEMAIL_FROM,MIME_QP_LONG_LINE,RCVD_IN_DNSWL_LOW,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of urgisb@gmail.com designates 209.85.161.179 as permitted sender) Received: from [209.85.161.179] (HELO mail-gx0-f179.google.com) (209.85.161.179) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 04 Dec 2010 03:05:16 +0000 Received: by gxk21 with SMTP id 21so5867152gxk.38 for ; Fri, 03 Dec 2010 19:04:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:subject:references:from :content-type:x-mailer:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; bh=enfNf9V01f8g6AOZzHi1grKVNpWio0K0x5wPg9V+FwU=; b=fUk3sX9E2L/GFhfzTLrMp71NYLTNrK/CpWcGRSwtx/KpxKutJ9HvjpOadteIQUvv0E 2wDGwapPPx2K2me1GnlNQbGHtamxv4nj0nGVdcpP2vu4bKQfHs+4qvDsclHw1uqqRna4 e3FHocIQgkW91XNToRZtvfxssOmhzqGUhyWQ8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:references:from:content-type:x-mailer:in-reply-to :message-id:date:to:content-transfer-encoding:mime-version; b=sti+18LX/JpTInyRgDj9cXpaYU0aldtczwjd4tn5pfmaFcmUjZwlfd+Vgy/rlo40vs /N6NIjT21jEomH1HMvMzbPeIVJslfpUNc5ZH0XrEUdTxMoZEfZaMEkwLgschkd2ftXn+ gPIu9lCitTM5vjNWN52o4L3MOMGxqSXxAY7I0= Received: by 10.151.49.5 with SMTP id b5mr5197163ybk.49.1291431895401; Fri, 03 Dec 2010 19:04:55 -0800 (PST) Received: from [192.168.1.4] (c-67-180-128-223.hsd1.ca.comcast.net [67.180.128.223]) by mx.google.com with ESMTPS id v8sm1520141yhg.40.2010.12.03.19.04.53 (version=TLSv1/SSLv3 cipher=RC4-MD5); Fri, 03 Dec 2010 19:04:54 -0800 (PST) Subject: Re: Is it pissible get a number of mapper tasks? References: From: Jason Content-Type: text/plain; charset=us-ascii X-Mailer: iPhone Mail (8C148) In-Reply-To: Message-Id: <99A93664-0CF1-4489-A5EB-57C8CAA38273@gmail.com> Date: Fri, 3 Dec 2010 19:04:48 -0800 To: "mapreduce-user@hadoop.apache.org" Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (iPhone Mail 8C148) > BTW, why not take task attempt id context.getTaskAttemptID() as the > prefix of unique id ? The task attempt id for each task should be > different The reason is that I would prefer to not have big gaps in my int id sequence= , so i'd rather store mapper task ID in the low bits (suffix instead of pref= ix) thus I need to know total number of Mappers. Thanks >>=20