[SOLR-17149] Cannot backup/restore large collection.

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 9.4
• Fix Version/s: 9.5
• Assignee: Jason Gerlowski
• Reporter: Pierre Salagnac
• Created: 05/Feb/24 19:21
• Updated: 12/Feb/24 19:48
• Resolved: 06/Feb/24 16:04

Description

 

There is a regression introduced in version 9.4 with SOLR-16879.

 

We cannot backup collections with more than 10 shards per node. The thread pool is rejecting new tasks with following error:

SolrException: Could not backup all shards

Task org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor$$Lambda... rejected from org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor[Running, pool size = 5, active threads = 5, queued tasks = 5, completed tasks = 30]"

expensiveExecutor thread pool executor is created with 5 max threads and bounded queue of the same size (5), so the total number of tasks is limited to 10 and all the other tasks are immediately rejected.

Issue Links

• is caused by: SOLR-16879 Throttle concurrent backups/restores per node
• links to: GitHub Pull Request #2243