Slower form displays after migration from CF MX 6.1

I migrated an application from CF MX 6.1 on WS2003 32-bit to Lucee on WS2008 R2 64-bit. Both are VMs running under VMware 6.7. Backend uses MS SQL Server on another VM.

Queries and logic are working fine. Lucee compatibility with CF is excellent. Yet some forms take significantly longer to display. For example, on our login page you can see table elements being displayed gradually whereas with CF they display almost instantaneously. Forms on the Lucee Administrator load quickly so its likely related to something in our logic.

Lucee administrator shows peak heap and CPU usage under 50%. Heap min/max are set to 512/1024.

Query times reported when debugging is on seem consistent with CF. The login page only spends 80 to 120 ms (total) in queries, which doesn’t explain the visible display lags.

Any suggestions would be appreciated. Thanks.

Version Lucee
Servlet Container Apache Tomcat/9.0.35
Java 11.0.7 (AdoptOpenJDK) 64bit
Microsoft SQL Server JDBC Driver 7.2.2.jre8
OS Windows Server 2008 R2 (6.1) 64bit

Did you look also into the network tab of chromes inspector? Maybe you can see something happening there.

Is it straight html or cfform/cfinput?
Is it a lot of data on screen?

the thing is, unless you’re cfflush-ing, Lucee only outputs html once the page is finished generating.

how long and large is the output in dev tools? ie. 50ms, 2mb

Thanks for your suggestions.

Comparing the HTML generated by Lucee and CF (attached as static.html and static2.html) points to a possible culprit. The lag occurs when the script “/lucee/formtag-form.cfm” is executed. There is no lag if that script is removed. Can that script be suppressed? or is there a way to optimize it? The Lucee Administrator login does not invoke that script. The HTML generated by CF does not invoke a similar script.

<script language = "JavaScript" type="text/javascript" src="/lucee/formtag-form.cfm"></script>

static.html (2.9 KB)
static2.html (3.2 KB)

Press F8 (pause JavaScript debugger) as it slowly renders?