[SOLR-5780] Solr should benefit from Guava 16.0.1

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 4.7
• Component/s: SolrCloud

Environment

All.

• Assignee: Unassigned
• Reporter: Guido Medina
• Created: 26/Feb/14 22:12
• Updated: 02/Feb/19 20:57
• Resolved: 02/Feb/19 20:57

Description

Solr is using concurrentlinkedhashmap v1.2 and Guava 14.0.1 at the same time, according to concurrentlinkedhashmap author(s), that project main objective is to introduce ideas and then when proven they are ported to Guava.

concurrentlinkedhashmap v1.2 was designed for Java 5 and v1.4 for Java 6+ which is the target version Solr 4.x requires, v1.4 had a great improvement in performance and memory impact compared to v1.2 which was ported to Guava (I strongly believe v16.0.1+ will do)

Pertinent material:

• http://stackoverflow.com/questions/15299554/what-does-it-mean-that-concurrentlinkedhashmap-has-been-integrated-into-guava
• https://code.google.com/p/concurrentlinkedhashmap/wiki/Changelog

All that said, concurrentlinkedhashmap should be eliminated - OR keep up to date because it is the core of in-memory cache, same as Guava - and code using it should instead use MapMaker builder from Guava.

Issue Links

• relates to: SOLR-11763 Upgrade Guava to 25.1-jre