| Proposed API change to IMessageHandler to address editor performance issue w/ many annotations [message #525409] |
Tue, 06 April 2010 10:01 |
Eclipse User |
|
|
|
Hi Everyone,
I just did some performance diagnosis/tuning work relating to
https://bugs.eclipse.org/bugs/show_bug.cgi?id=281359 .
*** Problem: ***
In a nutshell, when there were many error annotations on a source file,
say, many dozens or hundreds, the editor became unusably slow.
*** Diagnosis: ***
The main problem was that each message produced by IParseController.parse()
was directly applied as an "annotation model" update, via calls to Eclipse
JFace text API methods. Since UI updates are driven by annotation model
listeners, this approach caused many unnecessary UI updates; hence the slowdown.
*** Solution: ***
Luckily, I've discovered an extension to the IAnnotationModel interface –
IAnnotationModelExtension, which has extra API calls that allow you to submit
a group of annotation changes as a single batch. The result is that rather
than updating the model, and most importantly, all the annotation model
listeners, with each new Annotation, this cycle happens just once. The
performance improvement is rather dramatic: orders of magnitude.
*** Proposed IMP API change: ***
To achieve the full improvement described above, though, requires a small API
change to IMP's IMessageHandler interface, which doesn't presently have an API
call to notify when the producer of messages is finished producing messages
from a parsing/analysis session.
In particular, I'd like to add the following method:
public interface IMessageHandler {
// ...
/**
* Marks the end of a session of messages.
*/
void endMessages();
// ...
}
Now, most of the implementations of IMessageHandler that I'm aware of are in
IMP itself, which consumes the diagnostic output of an IParseController
implementation. So, I'd expect that the impact of such an API change would be
negligible, if anything.
That said, technically, this would be a breaking API change, so I need to ask
you all whether this will cause you any problem.
Comments?
--
Cheers,
-- Bob
--------------------------------
Robert M. Fuhrer
Research Staff Member
Programming Technologies Dept.
IBM T.J. Watson Research Center
IDE Meta-tooling Platform Project Lead (http://www.eclipse.org/imp)
X10: Productive High-Performance Parallel Programming (http://x10.sf.net)
|
|
|
Powered by
FUDForum. Page generated in 0.03174 seconds
Home