Eclipse Mars is too slow after ubuntu 16.04 update

The java process uses up almost 150% of the CPU. I have increased memory in eclipse.ini as well , removed unnecessary plugins, disabled spelling check, formatting etc.

Still it works very slow.

Solution

I encountered this problem Using Linux 16.04 and Mars.2

The issue is known and well documented here. https://bugs.eclipse.org/bugs/show_bug.cgi?id=430736#c35

Essentially there is a problem with GDK being used by Mars and what is in Ubuntu/Deb.

Fix is simple, add the following to your Eclipse.ini

--launcher.GTK_version
2

If your next question is. Where would I add those TWO lines? Here is a sample file, yours may differ, but it shows where to add the above.

$ cat eclipse.ini 
-startup
plugins/org.eclipse.equinox.launcher_1.3.0.v20140415-2008.jar
--launcher.library
plugins/org.eclipse.equinox.launcher.gtk.linux.x86_64_1.1.200.v20140603-1326
-product
org.eclipse.epp.package.cpp.product
--launcher.defaultAction
openFile
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.defaultAction
openFile
--launcher.GTK_version
2
--launcher.appendVmargs
-vmargs
-Dosgi.requiredJavaVersion=1.7
-XX:MaxPermSize=256m
-Xms40m
-Xmx1536m