Spring Tool Suite Really Slow

Question

I am running a Spring Boot project using the Spring Boot run configuration to run/debug the application. It is painfully slow, even on a very powerful computer. It often goes away for several seconds at time, not allowing the window to come to the front or to restoring the console back from maximized. Does anyone have any suggestions as to what might make it so slow?

Spring Tool Suite 

Version: 3.8.4.RELEASE
Build Id: 201703310825
Platform: Eclipse Neon.3 (4.6.3)

on a new Core i7 with 32GB of memory.

STS.ini has

-startup
plugins/org.eclipse.equinox.launcher_1.3.201.v20161025-1711.jar
--launcher.library
plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.1.401.v20161122-1740
-product
org.springsource.sts.ide
--launcher.defaultAction
openFile
-vmargs
-Dosgi.requiredJavaVersion=1.8
-Xms1024m
-Dosgi.module.lock.timeout=10
-Xverify:none
-Dorg.eclipse.swt.browser.IEVersion=10001
-Xmx4096m
-XX:PermSize=128m
-XX:MaxPermSize=512m
-XX:+UseParallelGC

Answer 1

The issue I ran into related to themes after a recent update from STS 3.7 to 3.9.5. Once I disabled theming through the following, most of the latency disappeared.

Preferences > General > Appearance > Enable theming

Since I wanted themes (Dark), I found that the most latent operation was scrolling through the Console when a server was started, or switch to and from that view. I found the following bug reported, and had success after disabling themed scrollbars by updating the following in e4-dark_win.css:

StyledText {
    swt-scrollbar-themed: false;
[...]

Beyond that, I also had to disable:

Preferences > Ansi Console

As well as:

Run configurations (select your Spring Boot App) > Spring Boot tab > ANSI console output