Return-Path: X-Original-To: apmail-hbase-user-archive@www.apache.org Delivered-To: apmail-hbase-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 426259F66 for ; Tue, 8 Nov 2011 23:54:10 +0000 (UTC) Received: (qmail 30402 invoked by uid 500); 8 Nov 2011 23:54:08 -0000 Delivered-To: apmail-hbase-user-archive@hbase.apache.org Received: (qmail 30362 invoked by uid 500); 8 Nov 2011 23:54:08 -0000 Mailing-List: contact user-help@hbase.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@hbase.apache.org Delivered-To: mailing list user@hbase.apache.org Received: (qmail 30354 invoked by uid 99); 8 Nov 2011 23:54:08 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 08 Nov 2011 23:54:08 +0000 X-ASF-Spam-Status: No, hits=3.4 required=5.0 tests=FREEMAIL_FROM,HTML_MESSAGE,RCVD_IN_DNSWL_LOW,SPF_PASS,URIBL_JP_SURBL X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of nkeywal@gmail.com designates 74.125.82.169 as permitted sender) Received: from [74.125.82.169] (HELO mail-wy0-f169.google.com) (74.125.82.169) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 08 Nov 2011 23:54:02 +0000 Received: by wyg24 with SMTP id 24so1466961wyg.14 for ; Tue, 08 Nov 2011 15:53:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=qVmyuhwzAWeQMDPZfhEY28aIl07/fwVAmnHCJzhhlww=; b=WlC/7ILEp7ZL0TGHjS82T2T1sfIM4l1DU+Zpey7lnPaOi26PQIsspNgFQ0KVf2+dYy Ix4vh+qSoMSNhB7OAO+5kEoY4T8WNuT7sqyJdpIeBXmx90S8X6zxHLv6yBsu+FyetDir r/x+oRzxDrxsweNYHlraQ9RHz0sTYAt+VmH/4= MIME-Version: 1.0 Received: by 10.216.229.34 with SMTP id g34mr4454972weq.37.1320796421743; Tue, 08 Nov 2011 15:53:41 -0800 (PST) Received: by 10.216.210.148 with HTTP; Tue, 8 Nov 2011 15:53:41 -0800 (PST) In-Reply-To: References: Date: Wed, 9 Nov 2011 00:53:41 +0100 Message-ID: Subject: Re: hbase heap size beyond 16G ? From: N Keywal To: user@hbase.apache.org Content-Type: multipart/alternative; boundary=0016e646998689e63404b141e14c X-Virus-Checked: Checked by ClamAV on apache.org --0016e646998689e63404b141e14c Content-Type: text/plain; charset=ISO-8859-1 If your're interested, some good slides on GC (slide 45 and after): http://www.azulsystems.com/sites/www.azulsystems.com/SpringOne2011_UnderstandingGC.pdf On Tue, Nov 8, 2011 at 11:25 PM, Mikael Sitruk wrote: > Concurrent GC (a.k.a CMS) does not mean that there is no more pause. The > pauses are reduced to minimum but can still happen especially if the > concurrent thread will not finish their work under high pressure. The G1 > collector in JDK 7.0 pretends to be a better collector than CMS, but i > presume tests will need to be done to validate this. > BTW the CMS collector is the one that is recommented in the book. > > Mikael.S > > On Tue, Nov 8, 2011 at 11:57 PM, Sujee Maniyam wrote: > > > HI All > > the HBase book by Lars warns it is not recommended to set heap size above > > 16G, because of 'stop the world' GC. > > > > Does this still apply? Specially with 'concurrentGC' ? > > > > thanks > > Sujee > > http://sujee.net > > > > > > -- > Mikael.S > --0016e646998689e63404b141e14c--