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 B4D65DE33 for ; Mon, 10 Dec 2012 20:14:27 +0000 (UTC) Received: (qmail 45688 invoked by uid 500); 10 Dec 2012 20:14:22 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 45646 invoked by uid 500); 10 Dec 2012 20:14:22 -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 45595 invoked by uid 99); 10 Dec 2012 20:14:22 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 10 Dec 2012 20:14:22 +0000 X-ASF-Spam-Status: No, hits=-0.0 required=5.0 tests=RCVD_IN_DNSWL_LOW,SPF_NEUTRAL X-Spam-Check-By: apache.org Received-SPF: neutral (athena.apache.org: local policy) Received: from [209.85.223.171] (HELO mail-ie0-f171.google.com) (209.85.223.171) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 10 Dec 2012 20:14:17 +0000 Received: by mail-ie0-f171.google.com with SMTP id 17so11542746iea.16 for ; Mon, 10 Dec 2012 12:13:57 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:x-gm-message-state; bh=VD9vkrZutaH9dMeCaq785PnYqM9CyWWa113jAr0Gr4w=; b=G/34pOweWVKigYDavUurFTylBlZQjB/yqcfnhJ1yKXyvQj3F9QCdP6sxADuoDwTCd5 vYD+tjVSluC8cV9xBNAUqM9NtaN/eklO+cdvBUzEP6i+ao0Fii1ydafi8dLOgktVELhh vTHoWe6YgCv+K1vffuOkgUMt8CtLUygUCF7Gcn0Lit5FRiB3H4fCnQCXMxaOpWH6Kewf Avv+pws6JylmHGlyQIZmvpcUkfpOWSSu02XTKNwBFD6kz/dRXDmz1kPgW49NQadC3kx7 ALTSr669vRJA9++R7yK+gA4wEzqRaM0uo1i0rY4NgwY7mAIjWHjDWOH2yhisJ0A3vf7c B/bw== MIME-Version: 1.0 Received: by 10.50.157.162 with SMTP id wn2mr7897457igb.27.1355170436872; Mon, 10 Dec 2012 12:13:56 -0800 (PST) Received: by 10.50.192.138 with HTTP; Mon, 10 Dec 2012 12:13:56 -0800 (PST) In-Reply-To: References: <81D05238-BD4C-46C4-AAAA-CD6A68CF7567@thelastpickle.com> Date: Mon, 10 Dec 2012 12:13:56 -0800 Message-ID: Subject: Re: Help on MMap of SSTables From: Rob Coli To: user@cassandra.apache.org Content-Type: text/plain; charset=ISO-8859-1 X-Gm-Message-State: ALoCoQkwEw8Isy81Q4Te/d2NOnwX9X8QzprcUQtllF9ybFUc9UjK8d68NSY9tB+ysrHxkXp+xAto X-Virus-Checked: Checked by ClamAV on apache.org On Thu, Dec 6, 2012 at 7:36 PM, aaron morton wrote: > So for memory mapped files, compaction can do a madvise SEQUENTIAL instead > of current DONTNEED flag after detecting appropriate OS versions. Will this > help? > > > AFAIK Compaction does use memory mapped file access. The history : https://issues.apache.org/jira/browse/CASSANDRA-1470 =Rob -- =Robert Coli AIM>ALK - rcoli@palominodb.com YAHOO - rcoli.palominob SKYPE - rcoli_palominodb