I have an application that executes this piece of code (JQuery 1.4.2) in an ASPX page for each element in the HTML table (500x)

```
$(".ArtRow_" + artId).each(function () {  
 if ($(this).find(".ArtOpen_" + artId).length <= 0) return; 
.... };

```

omitting the line with `find` makes this page load normally, but with the find:

* firefox & chrome: +- 3sec
* in IE9: +- 42 sec ( using 50% cpu on a dual core )

I did a profile in IE, and 95% of the time, IE is executing the function `CLASS` ( call stack:`find.f.filter.CLASS` ) 

I tried 

* using an Id with the find
* eleminated string concatination by using a fixed class

to no avail (42s)

Anyone a clue? Thanks in advance!

edit: Im convinced now that the each is taking so long. I skipped it, because with empty code block it didn't took 42 s to load . But with some lines of comment int it, it took again 42s, so i guess it was some kind of not very intelligent dead code detection.

on explicit request: the HTML where the ArtRow lives

```
 <tbody>
  <tr class="SB_ReceptielijstHeader">
    <th>Artikel / Bestelling</th>
    <th>Besteldatum</th>
    <th>Pr. School</th>
    <th>Pr. Levering</th>
    <th class="Number">Aantal besteld</th>
    <th class="Number">Aantal ontvangen</th>
  </tr>

  <tr class="SB_ReceptielijstArtikelHeader ArtRow_132109">
    <td id="Titel_132109" class="Artikel" colspan="5">
      <img src="images/SB/Icons/23-book.png" style="vertical-align:middle">&nbsp;9789030170433 - NANO 1</td>
      <td class="Number ArtikelTotal">
    <input type="hidden" value="132109" class="Artikel_Id">
      <input type="hidden" value="" id="ArtLevLn_132109">
        <input type="text" value="12" style="text-align:right" size="4" id="Aantal_132109" name="Aantal_132109" maxlength="4">
        </td>
      </tr>
      <tr class="SB_ReceptielijstRow ArtRow_132109 ArtRowInvisible">
        <td>Bestelling 81 / Lijn </td>
        <td>02/07/2010</td>
        <td>24,05</td>
        <td>22,85</td>
        <td class="ArtOpen_132109 Number">
        </td>
        <td id="ArtToew__132109" class="ArtToew ArtToew_132109 Number">
          <div style="display:none" class="ArtBestLn">
        <input type="hidden" value="">
        </div>
        <input type="text" style="text-align:right" size="4" id="Aantal_" name="Aantal_" maxlength="4"> 
        </td>
          </tr>

          <tr class="SB_ReceptielijstArtikelHeader ArtRow_134399">
        <td id="Titel_134399" class="Artikel" colspan="5">
          <img src="images/SB/Icons/23-book.png" style="vertical-align:middle">&nbsp;9789045533322 - HANDELWIJS 3 INCL CDROM HERWERKT 2010</td>
          <td class="Number ArtikelTotal">
            <input type="hidden" value="134399" class="Artikel_Id">
              <input type="hidden" value="" id="ArtLevLn_134399">
            <input type="text" value="25" style="text-align:right" size="4" id="Aantal_134399" name="Aantal_134399" maxlength="4">
            </td>
              </tr>
              <tr class="SB_ReceptielijstRow ArtRow_134399 ArtRowInvisible">
            <td>Bestelling 81 / Lijn </td>
            <td>02/07/2010</td>
            <td>23,95</td>
            <td>23,60</td>
            <td class="ArtOpen_134399 Number">
            </td>
            <td id="ArtToew__134399" class="ArtToew ArtToew_134399 Number">
              <div style="display:none" class="ArtBestLn">
                <input type="hidden" value="">
                </div>
                <input type="text" style="text-align:right" size="4" id="Aantal_" name="Aantal_" maxlength="4"> 
                </td>
              </tr>

            </tbody>

```