Return-Path: Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: (qmail 65439 invoked from network); 10 Feb 2011 20:25:12 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 10 Feb 2011 20:25:12 -0000 Received: (qmail 94619 invoked by uid 500); 10 Feb 2011 20:25:09 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 94570 invoked by uid 500); 10 Feb 2011 20:25:09 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 94562 invoked by uid 99); 10 Feb 2011 20:25:09 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 10 Feb 2011 20:25:09 +0000 X-ASF-Spam-Status: No, hits=0.0 required=5.0 tests=MIME_QP_LONG_LINE,RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: local policy) Received: from [208.113.200.5] (HELO homiemail-a41.g.dreamhost.com) (208.113.200.5) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 10 Feb 2011 20:25:03 +0000 Received: from homiemail-a41.g.dreamhost.com (localhost [127.0.0.1]) by homiemail-a41.g.dreamhost.com (Postfix) with ESMTP id 2591144C06E for ; Thu, 10 Feb 2011 12:24:42 -0800 (PST) DomainKey-Signature: a=rsa-sha1; c=nofws; d=thelastpickle.com; h=subject :references:from:content-type:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; q=dns; s= thelastpickle.com; b=AQa+1RE4Dlk4DDd3+OSVbKHmVz9erO/tEbHclsZsrHC c7kVoqjpfHEtqr/3VNGFbHGKuUvyogANLO+nUBaa4250Vbs7POaj2c7Ess1T+s0F D4HjA0DHJTypn1L0ykrxObgpak+mY2AwvkEUIJNjfilzOf2o7n+lyZjm4y9wsSWc = DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=thelastpickle.com; h= subject:references:from:content-type:in-reply-to:message-id:date :to:content-transfer-encoding:mime-version; s=thelastpickle.com; bh=yqEuL0VvO8iKa4sRDgplwim5aH4=; b=FoY+dk88ijVhhqZ52qAx6iCbVWH+ hrskDoSga6RHZTh6WFPeMYgv7EPGT7xW/3SKAJELwGBiRJnTMlSNMTx1t8/2Pwop SJqB8X/Ep5hranjlrNzvnxmknfrZQ6E7BkspGqPz1b2yI+0mko4z3EI0HS8tRqaw awJqrltO3TixJBg= Received: from [115.189.235.138] (unknown [115.189.235.138]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: aaron@thelastpickle.com) by homiemail-a41.g.dreamhost.com (Postfix) with ESMTPSA id 9A34844C062 for ; Thu, 10 Feb 2011 12:24:40 -0800 (PST) Subject: Re: Calculating the size of rows in KBs References: From: Aaron Morton Content-Type: text/plain; charset=us-ascii X-Mailer: iPad Mail (8C148) In-Reply-To: Message-Id: <2D616EE2-71D0-4156-AA74-568AF670CDFB@thelastpickle.com> Date: Fri, 11 Feb 2011 09:24:32 +1300 To: "user@cassandra.apache.org" Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (iPad Mail 8C148) If you want to get the byte size of a particular row you will need to read i= t all back. If you connect with JConsole at look at you column families, there are attri= butes for the max, min and mean row sizes. In general the entire row only exists in memory when it is contained in the f= irst Memtable it's written to. It may then be partially or fully read from d= isk during subsequent reads or compactions. On disk format described here may help http://wiki.apache.org/cassandra/Arc= hitectureSSTable Hope that helps Aaron On 10/02/2011, at 11:56 PM, Aditya Narayan wrote: > How can I get or calculate the size of rows/ columns ? what are the > any overheads on memory for each column/row ?