Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-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 6115810B85 for ; Fri, 16 Aug 2013 23:47:35 +0000 (UTC) Received: (qmail 84677 invoked by uid 500); 16 Aug 2013 23:47:32 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 84651 invoked by uid 500); 16 Aug 2013 23:47:32 -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 84643 invoked by uid 99); 16 Aug 2013 23:47:32 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 16 Aug 2013 23:47:32 +0000 X-ASF-Spam-Status: No, hits=-0.7 required=5.0 tests=RCVD_IN_DNSWL_LOW,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of 8forty@gmail.com designates 209.85.213.52 as permitted sender) Received: from [209.85.213.52] (HELO mail-yh0-f52.google.com) (209.85.213.52) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 16 Aug 2013 23:47:24 +0000 Received: by mail-yh0-f52.google.com with SMTP id f11so366608yha.11 for ; Fri, 16 Aug 2013 16:47:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject :content-type:content-transfer-encoding; bh=UjNHxXz9LpMx5Qb47KzCmsO5wj9/7sY7X/KvbcvAJTU=; b=MIU8dA1dqik7E53p1HqVccfTohNPa3U/cRaH7i8KMzXLvh3216Gg4cw2h5Sf48uuHT lzTC8Wj0bNDU4le4XojtBuZ92Wvvk52tVy1sVtq8ZPDhfMVD/kEVhglNkzaCs6JO4W2t b42pyYUKaZS7NLZmJ/I3gbkRb0L8r/9AX8fLbWVUgPeToyk6YThkrxQHDnj5LBLy+cTa 9Xp0lst7C/kdUfXjQp+LPEhuzNGE2X8m/5sFy/P8YXwPtwDTHvw7kuFgUAUfLMqUQ7HR 9lJdg26LbLqC6gzJdXbTSkA8xNLTn2dUvahUcFqftdVfx0pICnk5Lk2H+loxy1tzDkIF ZSWQ== X-Received: by 10.236.27.196 with SMTP id e44mr207894yha.16.1376696823642; Fri, 16 Aug 2013 16:47:03 -0700 (PDT) Received: from [127.0.0.1] ([162.216.44.217]) by mx.google.com with ESMTPSA id v22sm280179yhn.12.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 16 Aug 2013 16:47:02 -0700 (PDT) Message-ID: <520EB9F3.8040702@gmail.com> Date: Fri, 16 Aug 2013 17:46:59 -0600 From: Keith Freeman <8forty@gmail.com> User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130804 Thunderbird/17.0.8 MIME-Version: 1.0 To: user@cassandra.apache.org Subject: write load while idle? Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Checked: Checked by ClamAV on apache.org I have a 3-node cluster running 1.2.8, and with no clients connected (for about an hour) opscenter is showing a heartbeat-like pattern for total writes in the "Cluster Reads & Writes" panel on the dashboard ranging from about 10/sec to 26/sec. Total reads on the other hand are showing a straight line hovering just barely above 0/sec. There are no compactions, etc. (the logs are totally quiet). Is this normal? I'm new to cassandra so maybe this is normal but I couldn't find an explanation in the docs and it seems pretty high for an idle system.