SpellCheckComponent performance

[Demian Katz]

I'm continuing to work on tuning my Solr server, and now I'm noticing that my 
biggest bottleneck is the SpellCheckComponent.  This is eating multiple seconds 
on most first-time searches, and still taking around 500ms even on cached 
searches.  Here is my configuration:

  <searchComponent name="spellcheck" 
class="org.apache.solr.handler.component.SpellCheckComponent">
    <lst name="spellchecker">
      <str name="name">basicSpell</str>
      <str name="field">spelling</str>
      <str name="accuracy">0.75</str>
      <str name="spellcheckIndexDir">./spellchecker</str>
      <str name="queryAnalyzerFieldType">textSpell</str>
      <str name="buildOnOptimize">true</str>
    </lst>
  </searchComponent>

I've done a bit of searching, but the best advice I could find for making the 
search component go faster involved reducing spellcheck.maxCollationTries, 
which doesn't even seem to apply to my settings.

Does anyone have any advice on tuning this aspect of my configuration?  Are 
there any extra debug settings that might give deeper insight into how the 
component is spending its time?

thanks,
Demian