We have migrated from Solr 5.4.1 to Solr 6.4.0 and the disk usage has increased.
We found hundreds of references to deleted index files being held by solr.
Before the migration, we had 15-30% of disk space used, after the migration we have 60-90% of disk space used.

We are using Solr Cloud with 2 collections.

The commands applied on the collections are:
- for incremental indexation mode: add, deleteById with commitWithin of 30 minutes
- for full indexation mode: add, deleteById, commit
- for switch between incremental and full mode: deleteByQuery, createAlias, reload
- there is also an autocommit every 15 minutes

We have seen the email "Solr leaking references to deleted files"  2016-05-31 which describe the same problem but the mentioned bugs are fixed.

We manually tried to force a commit, a reload and an optimize on the collections without effect.

Is a problem of configuration (merge / delete policy) or a possible regression in the Solr code ?

Thank you
Kelkoo SAS
Société par Actions Simplifiée
Au capital de € 4.168.964,30
Siège social : 158 Ter Rue du Temple 75003 Paris
425 093 069 RCS Paris

Ce message et les pièces jointes sont confidentiels et établis à l'attention exclusive de leurs destinataires. Si vous n'êtes pas le destinataire de ce message, merci de le détruire et d'en avertir l'expéditeur.
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB