Return-Path: Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: (qmail 33856 invoked from network); 5 Apr 2010 16:20:56 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 5 Apr 2010 16:20:56 -0000 Received: (qmail 22033 invoked by uid 500); 5 Apr 2010 16:20:55 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 22004 invoked by uid 500); 5 Apr 2010 16:20:55 -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 21996 invoked by uid 99); 5 Apr 2010 16:20:55 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 05 Apr 2010 16:20:55 +0000 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests=FREEMAIL_FROM,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of prescod@gmail.com designates 74.125.83.44 as permitted sender) Received: from [74.125.83.44] (HELO mail-gw0-f44.google.com) (74.125.83.44) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 05 Apr 2010 16:20:48 +0000 Received: by gwj20 with SMTP id 20so1050536gwj.31 for ; Mon, 05 Apr 2010 09:20:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:from:date:x-google-sender-auth:received:message-id :subject:to:content-type; bh=k+smmEt4Mcy3b40UofxqagB/MC6ijrtv1bkcQS8mDdc=; b=ViI7EVQipTSUY64hoAwFhRaggqVXY4vuuisAA2v+Neb5/LO5xL2EL0mLkrB+jEeyPj bu43LW85z3p0iLNhphUX/X6oaEd03avu04/uozfVXViHUoI2+DCDGnMJyU4jDtqpgPTD hjQkOJBT3ef4yHq+dP/AoJ7P9zoDzfulLGhek= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:content-type; b=kO8bQ4I2L9f4kNN8F9DQ2osWpLvsaXqaf5UX8hxeqC1I/Ax3JXfH9oaU/vAfPNEvrJ 50ZORQyPcFKWHRSKKlst8c4Gdj2Nvy/EBd/t2OI7YcuQQR0PLEdOTChvLEDY/Ek1DBkJ jF3+5otbyFUmMjw86gXbsyzIQD707yCB9k804= MIME-Version: 1.0 Sender: prescod@gmail.com Received: by 10.100.231.17 with HTTP; Mon, 5 Apr 2010 09:20:06 -0700 (PDT) In-Reply-To: <4BB99933.6030708@fourkitchens.com> References: <4BB98AC5.3040607@fourkitchens.com> <4BB99933.6030708@fourkitchens.com> From: Paul Prescod Date: Mon, 5 Apr 2010 09:20:06 -0700 X-Google-Sender-Auth: 522d4c1e122a61eb Received: by 10.101.150.12 with SMTP id c12mr12695875ano.237.1270484426424; Mon, 05 Apr 2010 09:20:26 -0700 (PDT) Message-ID: Subject: Re: Memcached protocol? To: user@cassandra.apache.org Content-Type: text/plain; charset=UTF-8 X-Virus-Checked: Checked by ClamAV on apache.org On Mon, Apr 5, 2010 at 1:02 AM, David Strauss wrote: > ... > > But your "write then read" model lacks the atomicity of the memcached > API. It's possible for two clients to read the same value. Do you have an example application where this particular side effect of eventual consistency is problematic? Obviously memcached and Cassandra are different because of eventual consistency. The question is whether they are different enough to break an inconvenient number of real applications. Do you depend on add returning a unique number to each client in an application you've deployed? I have always imagined it as being primarily for simple counters. Paul Prescod