[ 
https://issues.apache.org/jira/browse/SOLR-18327?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

ASF GitHub Bot updated SOLR-18327:
----------------------------------
    Labels: pull-request-available  (was: )

> Balance replicas API does not balance duplicate replicas on same node
> ---------------------------------------------------------------------
>
>                 Key: SOLR-18327
>                 URL: https://issues.apache.org/jira/browse/SOLR-18327
>             Project: Solr
>          Issue Type: Bug
>            Reporter: Jan Høydahl
>            Assignee: Jan Høydahl
>            Priority: Critical
>              Labels: pull-request-available
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> The BALANCE_REPLICAS API (OrderedNodePlacementPlugin / 
> AffinityPlacementFactory) does not correct the situation where a node hosts 
> more than one replica of the same shard. Given a cluster where such 
> duplicates exist (e.g. created via ADDREPLICA with an explicit node, or 
> restore), a balance request computes an empty plan even though the cluster 
> violates the "one replica per shard per node" rule.
> *Reproduction:*
> 4 nodes, two collections, each with one shard of 4 NRT replicas placed 
> pairwise on two nodes (collection "a": 2 replicas on node 0, 2 on node 2; 
> collection "b": 2 on node 1, 2 on node 3). computeBalancing() returns zero 
> movements. See test testBalancingAvoidMultiReplicaOnNode in PR #2503 — fails 
> deterministically with "expected 4 computed 0" (verified with 
> -Dtests.iters=10).
> Fix in https://github.com/apache/solr/pull/2503



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to