From 28ede6aa71df11c08ee23d8306a3686e7d133cb0 Mon Sep 17 00:00:00 2001 From: Alan Conway Date: Thu, 16 May 2013 19:15:43 +0000 Subject: NO-JIRA: Add motivation for change to README-HA.txt. git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1483515 13f79535-47bb-0310-9956-ffa450edef68 --- qpid/cpp/README-HA.txt | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) (limited to 'qpid/cpp') diff --git a/qpid/cpp/README-HA.txt b/qpid/cpp/README-HA.txt index 03e190a3fc..d93c99d8f3 100644 --- a/qpid/cpp/README-HA.txt +++ b/qpid/cpp/README-HA.txt @@ -4,13 +4,19 @@ Migrating to new HA =================== Up to version 0.20, Qpid provided the `cluster` module to support active-active -clustering for Qpid C++ brokers. In version 0.20 the `ha` module was introduced -supporting active-passive HA clustering. From version 0.22 the older `cluster` -module is no longer available so users will have to migrate to the new `ha` -module. - -This document summarizes the differences between the old and new HA modules and -the steps to migrate to new HA. It assumes you have read the +clustering for Qpid C++ brokers. There were some issues with this module. It +relied on synchronization of too much broker state, so that unrelated changes to +the broker often required additional work on the cluster. It also had a design +that could not take advantage of multiple CPUs - it was effectively single +threaded. + +In version 0.20 the `ha` module was introduced supporting active-passive HA +clustering that does not suffer these problems. From version 0.22 the older +`cluster` module is no longer available so users will have to migrate to the new +`ha` module. + +This note summarizes the differences between the old and new HA modules and the +steps to migrate to new HA. It assumes you have read the [HA chapter of the C++ Broker Book][chapter-ha] Client connections and fail-over -- cgit v1.2.1