Are you able to identify if there is a particular part of the code that is slow?

A simple way to do this is to use the jstack command (assuming your server has 
the full JDK installed). You can run it like this:
/path/to/java/bin/jstack PID

If you run that a bunch of times while your highlight query is running, you 
might be able to spot the hotspot. Usually I'll do something like this to see 
the stacktrace for the thread running the query:
/path/to/java/bin/jstack PID | grep SearchHandler -B30

A few more questions:
- What are response times you are seeing before and after the upgrade? Is 
"unusably slow" 1 second, 10 seconds...?
- If you run the exact same query multiple times, is it consistently slow? Or 
is it only slow on the first run?
- While the query is running, do you see high user CPU on your server, or high 
IO wait, or both? (You can check this with the top command or vmstat command in 
Linux.)

-Michael

-----Original Message-----
From: Cheng, Sophia Kuen [mailto:sophia_ch...@hms.harvard.edu] 
Sent: Saturday, May 02, 2015 4:13 PM
To: solr-user@lucene.apache.org
Subject: Upgraded to 4.10.3, highlighting performance unusably slow

Hello,

We recently upgraded solr from 3.8.0 to 4.10.3.  We saw that this upgrade 
caused a incredible slowdown in our searches. We were able to narrow it down to 
the highlighting. The slowdown is extreme enough that we are holding back our 
release until we can resolve this.  Our research indicated using TermVectors & 
FastHighlighter were the way to go, however this still does nothing for the 
performance. I think we may be overlooking a crucial configuration, but cannot 
figure it out. I was hoping for some guidance and help. Sorry for the long 
email, I wanted to provide enough information.

Our documents are largely dynamic fields, and so we have been using ‘*’ as the 
field for highlighting. This is the same setting as in prior versions of solr 
use. The dynamic fields are of type ’text’ and we added customizations to the 
schema.xml for the type ’text’:

<fieldType name="text" class="solr.TextField" positionIncrementGap="100" 
storeOffsetsWithPositions="true" termVectors="true" termPositions="true" 
termOffsets="true">
  <analyzer type="index">
    <!--  this charFilter removes all xml-tagging from the text: -->
    <charFilter class="solr.HTMLStripCharFilterFactory"/>
    <tokenizer class="solr.WhitespaceTokenizerFactory"/>
    <!-- Case insensitive stop word removal.
      add enablePositionIncrements=true in both the index and query
      analyzers to leave a 'gap' for more accurate phrase queries.
    -->
    <filter class="solr.StopFilterFactory" ignoreCase="true" 
words="stopwords.txt" enablePositionIncrements="true"/>
    <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" 
generateNumberParts="1" catenateWords="1" catenateNumbers="1" catenateAll="0" 
splitOnCaseChange="1"/>
    <filter class="solr.LowerCaseFilterFactory"/>
    <filter class="solr.SnowballPorterFilterFactory" language="English" 
protected="protwords.txt"/>
  </analyzer>
  <analyzer type="query">
    <!--  this charFilter removes all xml-tagging from the text. Needed also in 
query due to autosuggest -->
    <charFilter class="solr.HTMLStripCharFilterFactory"/>
    <tokenizer class="solr.WhitespaceTokenizerFactory"/>
    <filter class="solr.StopFilterFactory" ignoreCase="true" 
words="stopwords.txt" enablePositionIncrements="true"/>
    <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" 
generateNumberParts="1" catenateWords="0" catenateNumbers="0" catenateAll="0" 
splitOnCaseChange="1"/>
    <filter class="solr.LowerCaseFilterFactory"/>
    <filter class="solr.SnowballPorterFilterFactory" language="English" 
protected="protwords.txt"/>
  </analyzer>
</fieldType>

One of the two dynamic fields we use:

<dynamicField name="DTPropValue_*"  type="text"    indexed="true"  
stored="true" required="false" multiValued="true"/>

In our solrConfig.xml file, we have:

<requestHandler name="/eiHandler" class="solr.SearchHandler"> <lst 
name="defaults"> <str name="echoParams">explicit</str>
     <int name="rows">13</int>
     <bool name="tv">true</bool>
     <bool name="hl.useFastVectorHighligter">true</bool>
   </lst>
<arr name="last-components">
<str>tvComponent</str>
</arr>
</requestHandler>
<searchComponent name="tvComponent" class="solr.TermVectorComponent”/>
<searchComponent class="solr.HighlightComponent" name="highlight">
  <highlighting>
    <fragmenter name="gap" default="true" class="solr.highlight.GapFragmenter">
      <lst name="defaults">
        <int name="hl.fragsize">100</int>
      </lst>
    </fragmenter>
    <fragmenter name="regex" class="solr.highlight.RegexFragmenter">
      <lst name="defaults">
        <int name="hl.fragsize">70</int>
        <float name="hl.regex.slop">0.5</float>
        <str name="hl.regex.pattern">[-\w ,/\n\&quot;&apos;]{20,200}</str>
      </lst>
    </fragmenter>

    <formatter name="html" default="true" class="solr.highlight.HtmlFormatter">
      <lst name="defaults">
        <str name="hl.simple.pre"><![CDATA[<i>]]></str>
        <str name="hl.simple.post"><![CDATA[</i>]]></str>
      </lst>
    </formatter>

    <encoder name="html" class="solr.highlight.HtmlEncoder" />
    <fragListBuilder name="simple" 
class="solr.highlight.SimpleFragListBuilder"/>
    <fragListBuilder name="single" 
class="solr.highlight.SingleFragListBuilder"/>
    <fragListBuilder name="weighted" default="true" 
class="solr.highlight.WeightedFragListBuilder"/>
    <fragmentsBuilder name="default" default="true" 
class="solr.highlight.ScoreOrderFragmentsBuilder">
    </fragmentsBuilder>

    <!-- multi-colored tag FragmentsBuilder -->
    <fragmentsBuilder name="colored" 
class="solr.highlight.ScoreOrderFragmentsBuilder">
      <lst name="defaults">
        <str name="hl.tag.pre"><![CDATA[
             <b style="background:yellow">,<b style="background:lawgreen">,
             <b style="background:aquamarine">,<b style="background:magenta">,
             <b style="background:palegreen">,<b style="background:coral">,
             <b style="background:wheat">,<b style="background:khaki">,
             <b style="background:lime">,<b 
style="background:deepskyblue">]]></str>
        <str name="hl.tag.post"><![CDATA[</b>]]></str>
      </lst>
    </fragmentsBuilder>

    <boundaryScanner name="default" default="true" 
class="solr.highlight.SimpleBoundaryScanner">
      <lst name="defaults">
        <str name="hl.bs.maxScan">10</str>
        <str name="hl.bs.chars">.,!? &#9;&#10;&#13;</str>
      </lst>
    </boundaryScanner>

    <boundaryScanner name="breakIterator" 
class="solr.highlight.BreakIteratorBoundaryScanner">
      <lst name="defaults">
        <str name="hl.bs.type">WORD</str>
        <str name="hl.bs.language">en</str>
        <str name="hl.bs.country">US</str>
      </lst>
    </boundaryScanner>
  </highlighting>
</searchComponent>

And in our code:

final SolrQuery query = new SolrQuery( luceneQueryStr ); 
query.setRequestHandler("/eiHandler");
query.setStart( request.getStartIndex() ); query.setRows( 
request.getMaxResults() ); query.setSort(new 
SortClause(request.getSortOrder().getFieldName(), 
request.getSortOrder().isAscending()?ORDER.asc:ORDER.desc) ); 
query.addHighlightField( "*" ); query.setFields( "*", "score" );

Any assistance is greatly appreciated.  Thank you.

Sincerely,
Sophia

Reply via email to