[
https://issues.apache.org/jira/browse/SOLR-11882?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17351751#comment-17351751
]
David Smiley commented on SOLR-11882:
-------------------------------------
[~ab] I'm looking very closely at the SolrDispatchFilter.close/destroy process
to ensure I understand every detail thoroughly. This
{{metricManager.unregisterGauges}} call was added in this JIRA issue
SOLR-11882. I'm guessing this change was not contributing to the memory leak
but other parts of this JIRA issue were because this memory leak is about
individual SolrCore leaks? Could/should it go to CoreContainer.close? Why
does SolrDispatchFilter have a reference to the MetricManager; can't it simply
look it up via CoreContainer.getMetricManager? Less state is better IMO.
> SolrMetric registries retain references to SolrCores when closed
> ----------------------------------------------------------------
>
> Key: SOLR-11882
> URL: https://issues.apache.org/jira/browse/SOLR-11882
> Project: Solr
> Issue Type: Bug
> Components: metrics, Server
> Affects Versions: 7.1
> Reporter: Eros Taborelli
> Assignee: Andrzej Bialecki
> Priority: Major
> Fix For: 7.4, 8.0
>
> Attachments: SOLR-11882-7x.patch, SOLR-11882.patch, SOLR-11882.patch,
> SOLR-11882.patch, SOLR-11882.patch, SOLR-11882.patch, SOLR-11882.patch,
> create-cores.zip, solr-dump-full_Leak_Suspects.zip, solr.config.zip
>
>
> *Description:*
> Our setup involves using a lot of small cores (possibly hundred thousand),
> but working only on a few of them at any given time.
> We already followed all recommendations in this guide:
> [https://wiki.apache.org/solr/LotsOfCores]
> We noticed that after creating/loading around 1000-2000 empty cores, with no
> documents inside, the heap consumption went through the roof despite having
> set transientCacheSize to only 64 (heap size set to 12G).
> All cores are correctly set to loadOnStartup=false and transient=true, and we
> have verified via logs that the cores in excess are actually being closed.
> However, a reference remains in the
> org.apache.solr.metrics.SolrMetricManager#registries that is never removed
> until a core if fully unloaded.
> Restarting the JVM loads all cores in the admin UI, but doesn't populate the
> ConcurrentHashMap until a core is actually fully loaded.
> I reproduced the issue on a smaller scale (transientCacheSize = 5, heap size
> = 512m) and made a report (attached) using eclipse MAT.
> *Desired outcome:*
> When a transient core is closed, the references in the SolrMetricManager
> should be removed, in the same fashion the reporters for the core are also
> closed and removed.
> In alternative, a unloadOnClose=true|false flag could be implemented to fully
> unload a transient core when closed due to the cache size.
> *Note:*
> The documentation mentions everywhere that the unused cores will be unloaded,
> but it's misleading as the cores are never fully unloaded.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@solr.apache.org
For additional commands, e-mail: issues-h...@solr.apache.org
