We have seen an increase between 4.8.1 and 4.10.
-----Original message-----
> From:Dmitry Kan <solrexp...@gmail.com>
> Sent: Tuesday 17th February 2015 11:06
> To: solr-user@lucene.apache.org
> Subject: unusually high 4.10.2 vs 4.3.1 RAM consumption
>
> Hi,
>
> We are currently comparing the RAM consumption of two parallel Solr
> clusters with different solr versions: 4.10.2 and 4.3.1.
>
> For comparable index sizes of a shard (20G and 26G), we observed 9G vs 5.6G
> RAM footprint (reserved RAM as seen by top), 4.3.1 being the winner.
>
> We have not changed the solrconfig.xml to upgrade to 4.10.2 and have
> reindexed data from scratch. The commits are all controlled on the client,
> i.e. not auto-commits.
>
> Solr: 4.10.2 (high load, mass indexing)
> Java: 1.7.0_76 (Oracle)
> -Xmx25600m
>
>
> Solr: 4.3.1 (normal load, no mass indexing)
> Java: 1.7.0_11 (Oracle)
> -Xmx25600m
>
> The RAM consumption remained the same after the load has stopped on the
> 4.10.2 cluster. Manually collecting the memory on a 4.10.2 shard via
> jvisualvm dropped the used RAM from 8,5G to 0,5G. But the reserved RAM as
> seen by top remained at 9G level.
>
> This unusual spike happened during mass data indexing.
>
> What else could be the artifact of such a difference -- Solr or JVM? Can it
> only be explained by the mass indexing? What is worrisome is that the
> 4.10.2 shard reserves 8x times it uses.
>
> What can be done about this?
>
> --
> Dmitry Kan
> Luke Toolbox: http://github.com/DmitryKey/luke
> Blog: http://dmitrykan.blogspot.com
> Twitter: http://twitter.com/dmitrykan
> SemanticAnalyzer: www.semanticanalyzer.info
>
