[Solr Wiki] Update of "SolrPerformanceProblems" by ShawnHeisey

[Apache Wiki <wi...@apache.org>]

Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Solr Wiki" for change notification.

The "SolrPerformanceProblems" page has been changed by ShawnHeisey:
https://wiki.apache.org/solr/SolrPerformanceProblems?action=diff&rev1=68&rev2=69

Comment:
added note saying that better GC might prolong an OOME, but can't prevent it.

  
  ==== Reducing heap requirements ====
  
- /!\ Tuning your garbage collection parameters will '''''NOT''''' reduce the amount of memory that Solr requires!  It ''might'' make reclaiming memory more efficient, but it can do absolutely nothing to lower the amount of memory that the program needs.  It might make the high points in the sawtooth memory graph lower, but it won't do anything about the low points.  If you are running into an [[SolrPerformanceFactors#OutOfMemoryErrors|OutOfMemory]] error, a change to GC tuning will not help at all.
+ /!\ Tuning your garbage collection parameters will '''''NOT''''' reduce the amount of memory that Solr requires!  It ''might'' make reclaiming memory more efficient, but it can do absolutely nothing to lower the amount of memory that the program needs.  It might make the high points in the sawtooth memory graph lower, but it won't do anything about the low points.  If you are running into an [[SolrPerformanceFactors#OutOfMemoryErrors|OutOfMemory]] error, a change to GC tuning will not help.  More efficient garbage collection might cause the program to take longer until OOME occurs, but it cannot prevent it.
  
  Here is an incomplete list, in no particular order, of how to reduce heap requirements, based on the [[SolrPerformanceProblems#Java_Heap|list above]] for things that require a lot of heap: