Is that some tips to write dustjs template for faster render? node.js - node.js

Question

I use dustjs to render my mail content and I found that it's slow when render some bigger templates. Is any tips when write dustjs template to increase the render speed, or some good practice?
details:
my template consists of several components (more than 5), each component if different from others, there is one example of the component as follow:
<tr>
<td align="center" valign="top" bgcolor="#FFFFFF">
<table cellpadding="0" cellspacing="0" width="650">
<tr>
<td align="center">
<table width="590" border="0" cellspacing="0" cellpadding="0">
{#eq key=haveBanner value=1}
<tr>
<td height="105" align="center" valign="middle">
<img src="{bannerUrl|pictureUrl}" width="590" border="0">
</td>
</tr>
{:else}
<tr>
<td align="center">
<table cellpadding="0" cellspacing="0" width="590" height="75" style="border-top:solid 3px #343434">
<tr>
<td width="130" align="left" valign="middle">
<table border="0" cellspacing="0" cellpadding="0">
<tr>
<td align="left" height="55">
<img src="{sellerLogo|pictureUrl}" width="110" height="55">
</td>
</tr>
</table>
</td>
<td width="460" align="left">
<table border="0" cellspacing="0" cellpadding="0">
<tr>
<td align="left"><font style="font-family:arial;font-size:16px;color:#292929">{compName}</strong></td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
{/eq}
<tr>
<td>
<table border="0" cellpadding="0" cellspacing="0" style="border:solid 1px #dbdbdb" width="594">
<tr>
<td width="149" valign="top" style="border-right:solid 1px #dbdbdb">
<table width="146" cellspacing="0" cellpadding="0">
<tr>
{#eq key=selectedProductFlag value=1}
<td height="80" style="padding:20px 20px"><font style="font-family:arial;font-size:18px;color:#333333"><b>Promotion Products</b></font></td>
{:else}
<td height="80" style="padding:20px 20px"><font style="font-family:arial;font-size:18px;color:#333333"><b>Promotion Products</b></font></td>
{/eq}
</tr>
<tr>
<td align="center" height="26" valign="top">
<table width="119" border="0" cellspacing="0" cellpadding="0">
<tr>
<td style="border-top:solid 1px #e5e5e5"><img src="http://newimg.globalmarket.com/PA/edm/images/spacer.gif" height="1" width="1"></td>
</tr>
</table>
</td>
</tr>
{#finalProdGroupList}
<tr>
<td height="35" valign="top">
<table width="146" cellspacing="0" cellpadding="0">
<tr>
<td style="padding-left:25px"><font style="font-family:arial;font-size:12px;color:#484848">{prodGroupName}</font></td>
</tr>
</table>
</td>
</tr>
{/finalProdGroupList}
</table>
</td>
<td width="443" valign="top">
<table width="442" border="0" cellspacing="0" cellpadding="0">
<tr>
<td>
<table width="442" border="0" cellspacing="0" cellpadding="0" height="255">
<tr>
{#secondaryProducts}
{#productList spIdx=$idx}
{#eq key=$idx value=2}
<td align="center" valign="top" width="147">
{:else}
<td align="center" valign="top" style="border-right:solid 1px #dbdbdb" width="147">
{/eq}
<table border="0" cellspacing="0" cellpadding="0">
<tr>
<td height="146" align="center">
<img src="{photoUrl|pictureUrl}" border="0" width="126" height="126" alt="{fullProdName}">
</td>
</tr>
<tr>
<td align="center">
<table width="126" border="0" cellspacing="0" cellpadding="0">
<tr>
<td align="center">
<table cellpadding="0" cellspacing="0" width="126">
<tr>
<td align="left" height="33" valign="top" style="line-height:15px">
<font style="font-family:Arial;font-size:12px;color:#333333">{productName}</font>
</td>
</tr>
<tr>
<td align="left" height="20" valign="middle"><font style="font-family:Arial;font-size:12px;color:#999999">{certification}</font></td>
</tr>
<tr>
{#eq key=payForInqFlag value=1}
<td align="left" height="35" valign="middle"><img src="http://newimg.globalmarket.com/PA/edm/images/getprice2.png" width="128" height="25"></td>
{:else}
<td align="left" height="35" valign="middle"><img src="http://newimg.globalmarket.com/PA/edm/images/getprice2.png" width="128" height="25"></td>
{/eq}
</tr>
<tr>
<td height="7"></td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
{/productList}
{/secondaryProducts}
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>

Answer 1

Your problem is very likely the large amount of Dust filters you are using.
Example:
&{trackCodeData|gaTrackCode|dbTrackCode|entityId|entityType|edmpid|recId|userId|token|final}
Some of these filters are even being run in a loop. It looks like you are running well over 100 filters per render of this template. Filters are executed synchronously and serially, so Dust can't continue to render the template until the filter is done.
Without knowing what these filters do, it's hard to make specific recommendations about the filters themselves. However, you seem to use the same filters multiple times to output the same data. If possible, you should pregenerate this data and add it into the context instead of dynamically generating it.
You can gain a few more cycles by turning on whitespace compression, if you have it turned off:
dust.config.whitespace = false;
But Dust intrinsically is very fast. Without your filters, your template renders in around 3ms for me.