title: Avoid slow highlighting on Solr because of stemming
body: <p>I am quite new about using Solr, but would like to ask your help.
  I am developing an application which should be able to highlight the results of a query. For this I am using regex fragmenter:</p>
  
  <pre><code>&lt;highlighting&gt;
  &lt;fragmenter name="regex" class="org.apache.solr.highlight.RegexFragmenter"&gt;
  &lt;lst name="defaults"&gt;
    &lt;int name="hl.fragsize"&gt;500&lt;/int&gt;
    &lt;float name="hl.regex.slop"&gt;0.5&lt;/float&gt;
    &lt;str name="hl.pre"&gt;&lt;![CDATA[&lt;b&gt;]]&gt;&lt;/str&gt;
    &lt;str name="hl.post"&gt;&lt;![CDATA[&lt;/b&gt;]]&gt;&lt;/str&gt;
    &lt;str name="hl.useFastVectorHighlighter"&gt;true&lt;/str&gt;
    &lt;str name="hl.regex.pattern"&gt;[-\w ,/\n\"']{20,300}[.?!]&lt;/str&gt;
    &lt;str name="hl.fl"&gt;dokumentum_syn_query&lt;/str&gt;
  &lt;/lst&gt;
  </code></pre>
  
  <p>
     
  The field is indexed with term vectors and offsets:</p>
  
  <pre><code>&lt;field name="dokumentum_syn_query" type="huntext_syn" indexed="true" stored="true"   multiValued="true" termVectors="on" termPositions="on"  termOffsets="on"/&gt;
  &lt;fieldType name="huntext_syn" class="solr.TextField" stored="true" indexed="true" positionIncrementGap="100"&gt;
        &lt;analyzer type="index"&gt;
          &lt;tokenizer class="com.morphologic.solr.huntoken.HunTokenizerFactory"/&gt;
          &lt;filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords_query.txt" enablePositionIncrements="true" /&gt;
          &lt;filter class="com.morphologic.solr.hunstem.HumorStemFilterFactory"
          lex="/home/oroszgy/workspace/morpho/solrplugins/data/lex"
          cache="alma"/&gt;
          &lt;filter class="solr.LowerCaseFilterFactory"/&gt;
        &lt;/analyzer&gt;
          &lt;analyzer type="query"&gt;
            &lt;tokenizer class="solr.StandardTokenizerFactory"/&gt;
        &lt;filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords_query.txt" enablePositionIncrements="true" /&gt;
        &lt;filter class="com.morphologic.solr.hunstem.HumorStemFilterFactory"
          lex="/home/oroszgy/workspace/morpho/solrplugins/data/lex"
          cache="alma"/&gt;
            &lt;filter class="solr.SynonymFilterFactory" synonyms="synonyms_query.txt" ignoreCase="true" expand="true"/&gt;
          &lt;filter class="solr.LowerCaseFilterFactory"/&gt;
        &lt;/analyzer&gt;
  &lt;/fieldType&gt;
  </code></pre>
  
  <p>The highlighting works well, excepts that its really slow. I realized that this is because the highlighter/fragmenter does stemming for all the result documents again.</p>
  
  <p>Could you please help me why does it happen an how should I avoid this? (I thought that using fastvectorhighlighter will solve my problem, but it didn't)</p>