Return-Path: Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: (qmail 22644 invoked from network); 13 Apr 2011 00:17:11 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 13 Apr 2011 00:17:11 -0000 Received: (qmail 51658 invoked by uid 500); 13 Apr 2011 00:17:10 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 51629 invoked by uid 500); 13 Apr 2011 00:17:10 -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 51621 invoked by uid 500); 13 Apr 2011 00:17:10 -0000 Delivered-To: apmail-incubator-cassandra-user@incubator.apache.org Received: (qmail 51618 invoked by uid 99); 13 Apr 2011 00:17:10 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 13 Apr 2011 00:17:10 +0000 X-ASF-Spam-Status: No, hits=2.0 required=5.0 tests=FREEMAIL_FROM,SPF_NEUTRAL,T_TO_NO_BRKTS_FREEMAIL,URI_HEX X-Spam-Check-By: apache.org Received-SPF: neutral (athena.apache.org: 216.139.236.26 is neither permitted nor denied by domain of mohitanchlia@gmail.com) Received: from [216.139.236.26] (HELO sam.nabble.com) (216.139.236.26) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 13 Apr 2011 00:17:04 +0000 Received: from jim.nabble.com ([192.168.236.80]) by sam.nabble.com with esmtp (Exim 4.69) (envelope-from ) id 1Q9nlE-0003RR-FI for cassandra-user@incubator.apache.org; Tue, 12 Apr 2011 17:16:44 -0700 Date: Tue, 12 Apr 2011 17:16:44 -0700 (PDT) From: mcasandra To: cassandra-user@incubator.apache.org Message-ID: <1302653804466-6267234.post@n2.nabble.com> In-Reply-To: References: <1302633374663-6266221.post@n2.nabble.com> <1302641755259-6266726.post@n2.nabble.com> Subject: Re: flush_largest_memtables_at messages in 7.4 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit One thing I am noticing is that cache hit rate is very low even though my cache key size is 1M and I have less than 1M rows. Not sure why so many cache miss? Keyspace: StressKeyspace Read Count: 162506 Read Latency: 45.22479006928975 ms. Write Count: 247180 Write Latency: 0.011610943442026053 ms. Pending Tasks: 0 Column Family: StressStandard SSTable count: 184 Space used (live): 99616537894 Space used (total): 99616537894 Memtable Columns Count: 351 Memtable Data Size: 171716049 Memtable Switch Count: 543 Read Count: 162507 Read Latency: 317.892 ms. Write Count: 247180 Write Latency: 0.006 ms. Pending Tasks: 0 Key cache capacity: 1000000 Key cache size: 256013 Key cache hit rate: 0.33801452784503633 Row cache: disabled Compacted row minimum size: 182786 Compacted row maximum size: 5839588 Compacted row mean size: 537470 -- View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/flush-largest-memtables-at-messages-in-7-4-tp6266221p6267234.html Sent from the cassandra-user@incubator.apache.org mailing list archive at Nabble.com.