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 A598ED605 for ; Fri, 19 Oct 2012 11:04:56 +0000 (UTC) Received: (qmail 46947 invoked by uid 500); 19 Oct 2012 11:04:52 -0000 Delivered-To: apmail-hadoop-mapreduce-user-archive@hadoop.apache.org Received: (qmail 46696 invoked by uid 500); 19 Oct 2012 11:04:51 -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 46658 invoked by uid 99); 19 Oct 2012 11:04:50 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 19 Oct 2012 11:04:50 +0000 X-ASF-Spam-Status: No, hits=1.7 required=5.0 tests=FREEMAIL_ENVFROM_END_DIGIT,HTML_MESSAGE,RCVD_IN_DNSWL_LOW,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of aiden449@gmail.com designates 209.85.216.176 as permitted sender) Received: from [209.85.216.176] (HELO mail-qc0-f176.google.com) (209.85.216.176) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 19 Oct 2012 11:04:43 +0000 Received: by mail-qc0-f176.google.com with SMTP id n41so205895qco.35 for ; Fri, 19 Oct 2012 04:04:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=3wrpLnlpQ7cbQ2YiEvkbpMH/81/QfjiRieMJanCQXGM=; b=f3s1TjOswqCrRQZsAKaD5ast5ntiTeW1Byn90bGL/MKE5B41sRQR2FuCpfksNMSV/F zIbBdl/pjPZw6s2bE7PyLwp/xkJnljBmcWpzRzbrPeI2iOr0Kivqxh5Zfk/SGvCb3FTW 9KL5gAf9ns8zdLJZous3ipJwcB3kY7l2yf1AyDfgEHSq0pqf2xC0sAq5Sb6i1tpzJEcQ iJQoPd8D5PCQhfvEsVBBbaJNuxocM4HyIo92y2StPsK0EQ2QyphKdG2+VwYrexV+9VjH 8PDaUWkbxxhwhXld/OJuXjUw9OLCm6f0pP9pr0v/hWsVX5UUURMio2Xs9AzstKzQjRKj 1TCg== MIME-Version: 1.0 Received: by 10.224.223.19 with SMTP id ii19mr535889qab.74.1350644662938; Fri, 19 Oct 2012 04:04:22 -0700 (PDT) Received: by 10.224.29.11 with HTTP; Fri, 19 Oct 2012 04:04:22 -0700 (PDT) In-Reply-To: References: Date: Fri, 19 Oct 2012 12:04:22 +0100 Message-ID: Subject: =?GB2312?Q?Re=3A_=B4=F0=B8=B4=3A_OOM=2Fcrashes_due_to_process_number_limit?= From: Aiden Bell To: user@hadoop.apache.org Content-Type: multipart/alternative; boundary=20cf3074b4ac5a2d7104cc677767 X-Virus-Checked: Checked by ClamAV on apache.org --20cf3074b4ac5a2d7104cc677767 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: quoted-printable Yep, and then the entire OS can't fork new processes. On 19 October 2012 05:10, =D0=BB=C1=BC wrote: > what's the exactly OOM error message, is it sth like "OutOfMemoryError: > unable to create new native thread" ? > ------------------------------ > *=B7=A2=BC=FE=C8=CB:* Aiden Bell [aiden449@gmail.com] > *=B7=A2=CB=CD=CA=B1=BC=E4:* 2012=C4=EA10=D4=C218=C8=D5 22:24 > *=CA=D5=BC=FE=C8=CB:* user@hadoop.apache.org > *=D6=F7=CC=E2:* OOM/crashes due to process number limit > > Hi All, > > Im running quite a basic map/reduce job with 10 or so map tasks. During > the task's execution, the > entire stack (and my OS for that matter) start failing due to being unabl= e > to fork() new processes. > It seems Hadoop (1.0.3) is creating 700+ threads and exhausting this > resource. RAM utilisation is fine however. > This still occurs with ulimit set to unlimited. > > Any ideas or advice would be great, it seems very sketchy for a task that > doesn't require much grunt. > > Cheers! > > --=20 ------------------------------------------------------------------ Never send sensitive or private information via email unless it is encrypted. http://www.gnupg.org --20cf3074b4ac5a2d7104cc677767 Content-Type: text/html; charset=GB2312 Content-Transfer-Encoding: quoted-printable Yep, and then the entire OS can't fork new processes.

On 19 October 2012 05:10, =D0=BB=C1=BC &= lt;xieliang@xiaomi= .com> wrote:
what's t= he exactly OOM error message, is it sth like "OutOfMemoryError: unable= to create new native thread" ?
=B7= =A2=BC=FE=C8=CB: Aiden Bell [aiden449@gmail.com]
=B7=A2=CB=CD=CA=B1=BC=E4: 2012=C4=EA10=D4=C218=C8=D5 22:24
=CA=D5=BC=FE=C8=CB: user@hadoop.apache.org
=D6=F7=CC=E2: OOM/crashes due to process number limit

Hi All,

Im running quite a basic map/reduce job with 10 or so map tasks. During the= task's execution, the
entire stack (and my OS for that matter) start failing due to being unable = to fork() new processes.
It seems Hadoop (1.0.3) is creating 700+ threads and exhausting this resour= ce. RAM utilisation is fine however.
This still occurs with ulimit set to unlimited.

Any ideas or advice would be great, it seems very sketchy for a task that d= oesn't require much grunt.

Cheers!




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Never send sensitive or priv= ate information via email unless it is encrypted. http://www.gnupg.org
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