Return-Path: X-Original-To: archive-asf-public-internal@cust-asf2.ponee.io Delivered-To: archive-asf-public-internal@cust-asf2.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by cust-asf2.ponee.io (Postfix) with ESMTP id 988B9200BA3 for ; Thu, 20 Oct 2016 18:00:01 +0200 (CEST) Received: by cust-asf.ponee.io (Postfix) id 96FCF160AF2; Thu, 20 Oct 2016 16:00:01 +0000 (UTC) Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by cust-asf.ponee.io (Postfix) with SMTP id 10DBA160ACC for ; Thu, 20 Oct 2016 18:00:00 +0200 (CEST) Received: (qmail 3731 invoked by uid 500); 20 Oct 2016 15:59:59 -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 3689 invoked by uid 99); 20 Oct 2016 15:59:59 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 20 Oct 2016 15:59:59 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id A8B592C0D53 for ; Thu, 20 Oct 2016 15:59:59 +0000 (UTC) Date: Thu, 20 Oct 2016 15:59:59 +0000 (UTC) From: "Dikang Gu (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (CASSANDRA-12777) Optimize the vnode allocation for single replica per DC MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 archived-at: Thu, 20 Oct 2016 16:00:01 -0000 [ https://issues.apache.org/jira/browse/CASSANDRA-12777?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15592202#comment-15592202 ] Dikang Gu commented on CASSANDRA-12777: --------------------------------------- Cool, revert the change to the test, and rebase on trunk, https://github.com/DikangGu/cassandra/commit/fbadd16cf9fb144445db2d8afeb261a67313fd25 Thanks! > Optimize the vnode allocation for single replica per DC > ------------------------------------------------------- > > Key: CASSANDRA-12777 > URL: https://issues.apache.org/jira/browse/CASSANDRA-12777 > Project: Cassandra > Issue Type: Improvement > Reporter: Dikang Gu > Assignee: Dikang Gu > Fix For: 3.x > > > The new vnode allocation algorithm introduced in CASSANDRA-7032 is optimized for the situation that there are multiple replicas per DC. > In our production environment, most cluster only has one replica, in this case, the algorithm does not work perfectly. It always tries to split token ranges by half, so that the ownership of "min" node could go as low as ~60% compared to avg. > So for single replica case, I'm working on a new algorithm, which is based on Branimir's previous commit, to split token ranges by "some" percentage, instead of always by half. In this way, we can get a very small variation of the ownership among different nodes. -- This message was sent by Atlassian JIRA (v6.3.4#6332)