Return-Path: X-Original-To: apmail-cassandra-commits-archive@www.apache.org Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id AB902102BC for ; Thu, 19 Sep 2013 16:01:02 +0000 (UTC) Received: (qmail 85124 invoked by uid 500); 19 Sep 2013 16:01:01 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 84831 invoked by uid 500); 19 Sep 2013 16:00:57 -0000 Mailing-List: contact commits-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 commits@cassandra.apache.org Received: (qmail 84641 invoked by uid 99); 19 Sep 2013 16:00:53 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 19 Sep 2013 16:00:53 +0000 Date: Thu, 19 Sep 2013 16:00:53 +0000 (UTC) From: "Jonathan Ellis (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Assigned] (CASSANDRA-5863) Create a Decompressed Chunk [block] Cache MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/CASSANDRA-5863?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Jonathan Ellis reassigned CASSANDRA-5863: ----------------------------------------- Assignee: Pavel Yaskevich (was: Tyler Hobbs) > Create a Decompressed Chunk [block] Cache > ----------------------------------------- > > Key: CASSANDRA-5863 > URL: https://issues.apache.org/jira/browse/CASSANDRA-5863 > Project: Cassandra > Issue Type: New Feature > Components: Core > Reporter: T Jake Luciani > Assignee: Pavel Yaskevich > Fix For: 2.1 > > > Currently, for every read, the CRAR reads each compressed chunk into a byte[], sends it to ICompressor, gets back another byte[] and verifies a checksum. > This process is where the majority of time is spent in a read request. > Before compression, we would have zero-copy of data and could respond directly from the page-cache. > It would be useful to have some kind of Chunk cache that could speed up this process for hot data. Initially this could be a off heap cache but it would be great to put these decompressed chunks onto a SSD so the hot data lives on a fast disk similar to https://github.com/facebook/flashcache. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira