From 4c2703e8be7deb25702f83d6371907e954f11ec1 Mon Sep 17 00:00:00 2001 From: Cao Manh Dat Date: Fri, 9 Mar 2018 19:35:26 +0700 Subject: [PATCH] SOLR-12051: Update upgrade notes --- solr/CHANGES.txt | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/solr/CHANGES.txt b/solr/CHANGES.txt index 5e4bf518066..0da7b1a81f0 100644 --- a/solr/CHANGES.txt +++ b/solr/CHANGES.txt @@ -78,11 +78,13 @@ Upgrade Notes * LUCENE-8161: If you are using the spatial JTS library with Solr, you must upgrade to 1.15.0. This new version of JTS is now dual-licensed to include a BSD style license. -* SOLR-12051: By using term value introduced in SOLR-11702, a replica will know that it is in-sync with the leader or not. - If all the replicas who participate in the election are out-of-sync with previous leader, the election will hang for - leaderVoteWait before allowing out-of-sync with previous leader replicas become leader. Note that the new leader - still needs to contains more updates than any other active replicas in the same shard. Therefore by increasing - leaderVoteWait will increase the consistency (over availability) of the system. +* SOLR-12051: A new mechanism is introduced in SOLR-11702 to maintain consistency in SolrCloud between leader and replicas. + This mechanism lets Solr know whether a replica is in-sync with the leader or not, even when the leader is not live. + If all the replicas who participate in the leader election are out-of-sync with previous leader, the election will + pause until a timeout (named "leaderVoteWait") before allowing an out-of-sync replica to become leader. Note that the + new leader still needs to contains more updates than any other active replicas in the same shard. Therefore by + increasing leaderVoteWait will increase the consistency (over availability) of the system. The default value of + leaderVoteWait is 180,000 ms (3 minutes) and it can be adjusted in the "solrcloud" section of the solr.xml * SOLR-11957: The default Solr log file size and number of backups is raised to 32MB and 10 respectively