hl.maxAnalyzedChars seems does not work

[Min Yang]

Hi,
My situation is that highlight a text field(about 2M per document) costed
too much time(>1s).

So I want to limit the characters highlighter analyze.

These are my highlighting parameters, which seem to have no problem:

       <bool name="hl">true</bool>
       <str name="hl.fl">text</str>
       <int name="hl.snippets">1</int>
       <int name="hl.maxAnalyzedChars">200</int>
       <str name="f.text.hl.alternateField">text</str>
       <int name="hl.maxAlternateFieldLength">100</int>

The parameter hl.maxAlternateFieldLength seems does not work...