Return-Path: Delivered-To: apmail-incubator-cassandra-commits-archive@minotaur.apache.org Received: (qmail 33563 invoked from network); 19 Nov 2009 16:29:49 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 19 Nov 2009 16:29:49 -0000 Received: (qmail 70384 invoked by uid 500); 19 Nov 2009 16:29:48 -0000 Delivered-To: apmail-incubator-cassandra-commits-archive@incubator.apache.org Received: (qmail 70366 invoked by uid 500); 19 Nov 2009 16:29:48 -0000 Mailing-List: contact cassandra-commits-help@incubator.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: cassandra-dev@incubator.apache.org Delivered-To: mailing list cassandra-commits@incubator.apache.org Received: (qmail 70351 invoked by uid 99); 19 Nov 2009 16:29:48 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 19 Nov 2009 16:29:48 +0000 X-ASF-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: apache.org Received: from [140.211.11.130] (HELO eos.apache.org) (140.211.11.130) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 19 Nov 2009 16:29:46 +0000 Received: from eos.apache.org (localhost [127.0.0.1]) by eos.apache.org (Postfix) with ESMTP id 584B517D16; Thu, 19 Nov 2009 16:29:26 +0000 (GMT) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable From: Apache Wiki To: Apache Wiki Date: Thu, 19 Nov 2009 16:29:26 -0000 Message-ID: <20091119162926.19672.3075@eos.apache.org> Subject: =?utf-8?q?=5BCassandra_Wiki=5D_Update_of_=22FAQ=22_by_JonathanEllis?= Dear Wiki user, You have subscribed to a wiki page or wiki category on "Cassandra Wiki" for= change notification. The "FAQ" page has been changed by JonathanEllis. http://wiki.apache.org/cassandra/FAQ?action=3Ddiff&rev1=3D27&rev2=3D28 -------------------------------------------------- =3D=3D What kind of hardware should I run Cassandra on? =3D=3D = =3D=3D=3D Memory =3D=3D=3D - The most recently written data resides in memory tables (aka [[MemtableTh= resholds|memtables]]), but older data that has been flushed to disk can be = kept in the OS's file-system cache. In other words, ''the more memory, the = better'', (with 1GB being the absolute minimum). + The most recently written data resides in memory tables (aka [[MemtableTh= resholds|memtables]]), but older data that has been flushed to disk can be = kept in the OS's file-system cache. In other words, ''the more memory, the = better'', with 1GB being the minimum recommended. = =3D=3D=3D CPU =3D=3D=3D - FIXME + Many workloads will actually be CPU-bound in Cassandra before being memor= y-bound. Cassandra is highly concurrent and will make good use of however = many cores you can give it. + = = =3D=3D=3D Disk =3D=3D=3D The short answer here is, ''at least 2 disks'', one to keep your `CommitL= ogDirectory` on, the other to use in `DataFileDirectories`. The exact answe= r though depends a lot on your usage so it's important to understand what i= s going on here.