Performance improvements of GWT2.1 for long-based computations

[Lukas Laag]

I have just finished porting my chess game (http://www.vectomatic.org/
gwt/lib-gwt-svg-chess/lib-gwt-svg-chess.html) to GWT 2.1 and I would
like to report some performance measurements which highlight how much
the situation has improved for long-based computations with the
release of GWT2.1.

The application makes heavy use of java longs, notably in the attack
tables of its Carballo chess engine (the table contains 100 000+
longs). At the time the original code was written (one year ago), the
time to initialize the attack tables turned out to be so long (around
two and a half minutes) that I had to pre-compute them, causing a big
one-time penalty in the application download size (4MB download,
somewhat mitigated by the use of HTTP compression). Since then, GWT
has introduced a revamped emulation of java longs, and browsers
javascript engines are now much faster. I have been able to get rid of
the pre-computed tables and compute them on the fly. The execution
time for this part of the code is now (on my linux box):

| Browser | Ellapsed time to compute attack table
| FF3.6 | 23s
| Opera 10.63 | 14s
| Chrome 7.x | 0.5s
| FF4b7 | 3s

This certainly beats downloading 4MB of attack tables !

[Jeff Schwartz]

Those numbers are quite impressive but what I find equally impressive is just how much faster Chrome is over the other browsers, including FF beta. BTW I know GWT doesn't fully suppoMS IE9b but it would be interesting to see how stands in relation to the other browsers.

Jeff

--
You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group.
To post to this group, send email to google-we...@googlegroups.com.
To unsubscribe from this group, send email to google-web-tool...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/google-web-toolkit?hl=en.

--
Jeff

[Jeff Schwartz]

Sorry, I meant support MS IE9b.

--
Jeff

[Rodrigue Lagoue Njinthe]

Hi all,

I get a exception when trying to remove an entry from a LisProvider's list.
Hier is the stacktrace.

java.lang.UnsupportedOperationException: null
at java.util.AbstractList.remove(AbstractList.java:144)
at java.util.AbstractList$Itr.remove(AbstractList.java:360)
at java.util.AbstractCollection.removeAll(AbstractCollection.java:337)
at
com.google.gwt.view.client.ListDataProvider$ListWrapper.removeAll(ListDataPr
ovider.java:338)

The code that causes the error is:
ListProvider.getList().removeAll(Arrays.asList(data));

Thanks for any help
Rodrigue

--