Return-Path: Delivered-To: apmail-hadoop-common-user-archive@www.apache.org Received: (qmail 82265 invoked from network); 11 Apr 2011 23:06:07 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 11 Apr 2011 23:06:07 -0000 Received: (qmail 71479 invoked by uid 500); 11 Apr 2011 23:06:04 -0000 Delivered-To: apmail-hadoop-common-user-archive@hadoop.apache.org Received: (qmail 71430 invoked by uid 500); 11 Apr 2011 23:06:04 -0000 Mailing-List: contact common-user-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: common-user@hadoop.apache.org Delivered-To: mailing list common-user@hadoop.apache.org Received: (qmail 71422 invoked by uid 99); 11 Apr 2011 23:06:04 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 11 Apr 2011 23:06:04 +0000 X-ASF-Spam-Status: No, hits=-0.7 required=5.0 tests=FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of jason.rutherglen@gmail.com designates 209.85.216.169 as permitted sender) Received: from [209.85.216.169] (HELO mail-qy0-f169.google.com) (209.85.216.169) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 11 Apr 2011 23:05:58 +0000 Received: by qyk2 with SMTP id 2so1868046qyk.14 for ; Mon, 11 Apr 2011 16:05:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; bh=4zKq9XFSrlkIO9Xmpf9v8SSdv4YkW4LBTd6FxNnHGls=; b=pJDHfUFGl1W7U9ldSwEih0pwNmwziwlvfnI2jv37i7hZlyJgYqwmOPMfYuhI53K/T5 PcAyMJsIkdkIMMqlNG9WiC4biIBzIva9iOTFCyeVZEmln0k9eGhLM+CQCLSUaPBLRGP5 lO5TBi3UOZkzdNg9NyptcYmwlahNl8guNXQKM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=vx6IPY1/+NZzJ2RKYny4jIHff+hJU7t5kja/hzcR4A6fWiu0M2ATvlk0KtJAWymnPi a0XyGZpYU9SYy/3MYB0oZsikVf51VUSJfhVH1vZ16I2jEGJcDPGt0b9eBKPtKj5+pmhT 4Di+895FWq6IidW9InuVtiB8iS6ED+Frzomc0= MIME-Version: 1.0 Received: by 10.229.79.196 with SMTP id q4mr4703542qck.132.1302563137664; Mon, 11 Apr 2011 16:05:37 -0700 (PDT) Received: by 10.229.222.135 with HTTP; Mon, 11 Apr 2011 16:05:37 -0700 (PDT) In-Reply-To: References: Date: Mon, 11 Apr 2011 16:05:37 -0700 Message-ID: Subject: Re: Memory mapped resources From: Jason Rutherglen To: common-user@hadoop.apache.org Content-Type: text/plain; charset=ISO-8859-1 Yes you can however it will require customization of HDFS. Take a look at HDFS-347 specifically the HDFS-347-branch-20-append.txt patch. I have been altering it for use with HBASE-3529. Note that the patch noted is for the -append branch which is mainly for HBase. On Mon, Apr 11, 2011 at 3:57 PM, Benson Margulies wrote: > We have some very large files that we access via memory mapping in > Java. Someone's asked us about how to make this conveniently > deployable in Hadoop. If we tell them to put the files into hdfs, can > we obtain a File for the underlying file on any given node? >