Return-Path: Delivered-To: apmail-cassandra-dev-archive@www.apache.org Received: (qmail 42356 invoked from network); 7 Apr 2010 20:37:53 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 7 Apr 2010 20:37:53 -0000 Received: (qmail 59058 invoked by uid 500); 7 Apr 2010 20:37:52 -0000 Delivered-To: apmail-cassandra-dev-archive@cassandra.apache.org Received: (qmail 59041 invoked by uid 500); 7 Apr 2010 20:37:52 -0000 Mailing-List: contact dev-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@cassandra.apache.org Delivered-To: mailing list dev@cassandra.apache.org Received: (qmail 59033 invoked by uid 99); 7 Apr 2010 20:37:52 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 07 Apr 2010 20:37:52 +0000 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests=FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of jbellis@gmail.com designates 209.85.218.222 as permitted sender) Received: from [209.85.218.222] (HELO mail-bw0-f222.google.com) (209.85.218.222) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 07 Apr 2010 20:37:46 +0000 Received: by bwz22 with SMTP id 22so1296063bwz.25 for ; Wed, 07 Apr 2010 13:37:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :from:date:received:message-id:subject:to:content-type :content-transfer-encoding; bh=+fh3svi4KcJ0DlwKnKAKF5Hbft/cQ8zBzfU7J4FvSEE=; b=ChCbfvotytwnXk5H0dGROlfOiTcRGRmKYVRyQzYKrpcZhvESMVDy9zVFWBn1us4yHe 47JJUAJkhnU9B/OtOf8FZAdMCGTbqkvkaXdUn/cKqVCCpvTDJN6e1eFJbVghl3M4QFq/ Gl65QeaAtjaeuzc8q7DxLWnNEgO/Ts024Vyrg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type:content-transfer-encoding; b=KokI2L8kDIfnYVbftekeY7naNVq6jxdjZyL1YFYTFb80XLr+go1yj4m2rCi5/GLaH+ YRwYXPIUkSUEMuZGAJcOctoh/nNh0VrZlJycFzFpGnj/+KNvis9tDod/uuYLJ02HH7FE aI7rDIsIXEceC/s/TI9FdVynnLZyrBd9wy5ww= MIME-Version: 1.0 Received: by 10.204.104.1 with HTTP; Wed, 7 Apr 2010 13:37:05 -0700 (PDT) In-Reply-To: References: From: Jonathan Ellis Date: Wed, 7 Apr 2010 15:37:05 -0500 Received: by 10.204.38.77 with SMTP id a13mr9848233bke.26.1270672645525; Wed, 07 Apr 2010 13:37:25 -0700 (PDT) Message-ID: Subject: Re: boonfilters To: dev@cassandra.apache.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Virus-Checked: Checked by ClamAV on apache.org 2010/4/7 Peter Sch=FCller : > Someone correct me if I'm wrong, but my understanding is that the > bloom filters are only used to optimize the case of a key being > non-existent, such that you only have to go down on disk for a very > small number of requests for non-existent keys. I do not believe bloom > filters have any interaction with replication. The reason to use a > bloom filter is that it trades great memory efficiency for the > possibility of false positives. We also use row-level bloom filters when you request columns by name (as opposed to by slice). -Jonathan