Add notes for 2019-04-13

content/posts/2019-04.md

@@ -607,4 +607,18 @@ $ ./delete-metadata-values.py -i /tmp/2019-04-11-delete-6-subjects.csv -db dspac
   - They added a DOI to this old item [10567/97087](https://cgspace.cgiar.org/handle/10568/97087) this morning and wonder why Altmetric's score hasn't linked with the DOI magically
   - We should check in a week to see if Altmetric will make the association after one week when they harvest again
 
+## 2019-04-13
+
+- I copied the `statistics` and `statistics-2018` Solr cores from CGSpace to my local machine and watched the Java process in VisualVM while indexing item views and downloads with my [dspace-statistics-api](https://github.com/ilri/dspace-statistics-api):
+
+![Java GC during Solr indexing with CMS](/cgspace-notes/2019/04/visualvm-solr-indexing.png)
+
+- It took about eight minutes to index 784 pages of item views and 268 of downloads, and you can see a clear "sawtooth" pattern in the garbage collection
+- I am curious if the GC pattern would be different if I switched from the `-XX:+UseConcMarkSweepGC` to G1GC
+- I switched to G1GC and restarted Tomcat but for some reason I couldn't see the Tomcat PID in VisualVM...
+  - Anyways, the indexing process took much longer, perhaps twice as long!
+- I tried again with the GC tuning settings from the Solr 4.10.4 release:
+
+![Java GC during Solr indexing Solr 4.10.4 settings](/cgspace-notes/2019/04/visualvm-solr-indexing-solr-settings.png)
+
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