Return-Path: X-Original-To: apmail-kafka-dev-archive@www.apache.org Delivered-To: apmail-kafka-dev-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 862BF18DBB for ; Mon, 4 Jan 2016 23:22:40 +0000 (UTC) Received: (qmail 23583 invoked by uid 500); 4 Jan 2016 23:22:40 -0000 Delivered-To: apmail-kafka-dev-archive@kafka.apache.org Received: (qmail 23485 invoked by uid 500); 4 Jan 2016 23:22:40 -0000 Mailing-List: contact dev-help@kafka.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@kafka.apache.org Delivered-To: mailing list dev@kafka.apache.org Received: (qmail 23131 invoked by uid 99); 4 Jan 2016 23:22:40 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 04 Jan 2016 23:22:40 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id CFBA42C1F5C for ; Mon, 4 Jan 2016 23:22:39 +0000 (UTC) Date: Mon, 4 Jan 2016 23:22:39 +0000 (UTC) From: "xingang (JIRA)" To: dev@kafka.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (KAFKA-3062) Read from kafka replication to get data likely Version based 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/KAFKA-3062?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15081989#comment-15081989 ] xingang commented on KAFKA-3062: -------------------------------- "Likely version based" means: 1) it's Ok for such None-Latency consumers to fetch data slower than from the leaders. or even less of them 2) the consistency of replicas could be version-based synced, thus, the consumers can get the "None-dup, None-loss" eventually, No requirement to be consistent for a real-time It will be so GOOD in this way, No more extra storage required but get History/Realtime consuming separated > Read from kafka replication to get data likely Version based > ------------------------------------------------------------ > > Key: KAFKA-3062 > URL: https://issues.apache.org/jira/browse/KAFKA-3062 > Project: Kafka > Issue Type: Improvement > Reporter: xingang > > Since Kafka require all the reading happens in the leader for the consistency. > If there could be possible for the reading can happens in replication, thus, for data have a number of consumers, for the consumers Not latency-sensitive But Data-Loss sensitive can fetch its data from replication, in this case, it will pollute the Pagecache for other consumers which are latency-sensitive -- This message was sent by Atlassian JIRA (v6.3.4#6332)