Hello Tom,
I had to increase my free disk space to allow for the huge amount of files created. I had 280Gb free but increased it to 780Gb. It needed over 300GB.
I set the following:-
<Property name="wt.index.maxContentSize" overridable="true" targetFile="codebase/wt.properties" value="1048576"/>
<Property name="wt.index.maxDocumentSize" overridable="true" targetFile="codebase/wt.properties" value="10485760"/>
SOLR_HEAP set to 8192
I processed all objects types individually leaving documents till last (took around 1 day), I then processed the documents which took a further 4 days
I tested the same bulk index on my Test Windchill 12.0.2.10 and it takes around 1 1/2 days.
Conclusion: The performance of 13.0.2.4 bulk indexing takes 3 times as long as 12.0.2.10. Doing the above helped as It stopped the SOLR service from crashing and was faster than the first rehearsal. It needs fixing by PTC