Hi,
we've recently changed our Solr-Version from 6.2.1 to 7.5.0, and since then,
whenever we execute a query on solr, a new thread is being created and never
closed.
These threads are all labelled "Connection evictor" and the gather until a
critical mass is reached and either the OS cannot create anymore OS threads, or
an out of memory error is being produced.
First I thought, that this might have as cause we were using a higher
SolrJ-Version than our Solr-Server (by mistakenly forgetting to uprade the
server version too):
So we had for SolrJ: 7.4.0
<dependency>
<groupId>org.apache.solr</groupId>
<artifactId>solr-solrj</artifactId>
<version>7.4.0</version>
</dependency>
And for Solr-Server: 6.2.1
But now I just installed the newest Solr-Server-Version 7.5.0 and still I see
with each Solr-Search performed an additional Thread being created and never
released.
When downgrading SolrJ to 6.2.1 I can verify, that no new threads are created
when doing a solr search.
What do you think about this? Are there any known pitfalls? Maybe I missed some
crucial changes necessary when upgrading to 7.5.0?
What about differing versions in SolrJ and Solr-Server? As far as I recall the
docs, one major-version-difference up/down in both ways should be o.k.
Thanks for all your feedback,
Yours sincerely
Sebastian Riemer
