Eclipse Juno slow to switch tabs in editor

Question

In Eclipse Juno SR1 on OSX 10.8.2 Mountain Lion, Java version "1.6.0_37", a while after startup it becomes very slow to simply switch between tabs for source files being edited. The CPU goes to 100% and the editor freezes for several seconds before the new tab content is shown.

Upon reading about the problem I edited my eclipse.ini to have:

--launcher.XXMaxPermSize 2768M
-XX:MaxPermSize=2768M
-Xms440m
-Xmx2512m

As advised at http://wiki.eclipse.org/, and this only had the effect that now it takes longer after I restart Eclipse for the problem to start happening again.

I can't believe that on a machine with a SATAIII SSD, an i5 processor and 8GB of ram that switching tabs in a text editor could be so slow. Is there anything else I can try?

Answer 1

Juno and Juno SR1 have serious performance issue when open, close and switch editors.

Eclipse community has fixed lots of performance issues in upcoming Juno SR2 and Kepler M4. You can install maintenance build of Juno to have a try.

Answer 2

Edit: The SR1 patches are no longer the best option, as SR2 is already released. Use the latest Eclipse Juno (4.2.2) or Kepler (4.3) as soon as it is released (officially June 26).

---

If you don't want to install SR2 yet (official release date is in Feburary), there is a patch for Eclipse Juno SR1.

1. Invoke Help > Install New Software
2. Select this repository: http://download.eclipse.org/eclipse/updates/4.2
3. Expand Juno SR1 Patches and install Eclipse UI Juno SR1 Optimizations

Read more here: http://wiki.eclipse.org/Platform_UI/Juno_Performance_Investigation

Answer 3

I've experienced similar issues in Ubuntu and switching the General/Apperance/Theme setting to Classic helped a lot.

Answer 4

UPDATE : New performance release(SP2) for Eclipse Juno is out. So if your Eclipse Juno(4.2) is too slow or if it crashes intermittently it can be updated to SP2.

Just goto Help -> Check for Updates

P.S. Please backup your Eclipse folder before doing this.

ORIGNAL ANSWER:

This is a known issue in Eclipse Juno and there is a patch released for that. Installing this fixes the performance issues -

http://wiki.eclipse.org/Platform_UI/Juno_Performance_Investigation

Quote

Several major performance defects have been addressed in the Juno SR2 stream (4.2.2). Community members have confirmed that these fixes substantially address the performance problems with editor and view opening, closing, and switching. These fixes will be widely available in the Juno Service Release 2 (February 2013) and Kepler (June 2013) releases. Meanwhile, a patch is available for those using Juno SR1 that provides early access to these fixes. To install this patch:

Ensure you are already running on a package from the Juno SR1 release (September 2012) Invoke Help > Install New Software Select this repository: http://download.eclipse.org/eclipse/updates/4.2 Expand Juno SR1 Patches and install Eclipse UI Juno SR1 Optimizations To repeat, this patch is only intended for users of the Juno SR1 release. If you have a Juno SR2 maintenance build from November 21 or later, or Kepler stream milestone M4 or later, this patch is not required.