Working with some bigger Java EE 5 (glassfish) projects, netbeans 5.5 became really slow. Especially the response times
were not satisfactory. So I tried to improve the performance with some "old plain java methods" - I increased the heap space and it really helped.
To change the initial and max heap, netbeans configuration in [netbeans_home]/etc/netbeans.conf has to be changed.
I changed the -Xmx, as well as the -Xms setting - the default setting were amazingly low (32m and 128m).
netbeans_default_options="-J-Xms256m -J-Xmx512m ..."
I also changed the netbeans_jdkhome to Java SE6 from SE5.
After these changes netbeans became really fast, the speedup is remarkable.
Another optimization can be done directly in netbeans. The parsing delay can be reduced, so netbeans will parse you changes immediately.
Menu->Tools->Options[advanced options]->Editing->Java Sources.Automatic Parsing Delay=50
I changed it to 50ms, and it works on my notebook (old centrino CPU with 2.13 GHz, 2GB RAM) very well.
The value of the setting "Delay of Completion Window Auto Popup" (Editing->Editor Settings->Java Editor) can be also lowered.
One problem remains - opening of the fileexplorer is very slow. It is not a special netbeans, but a more general problem on my machine.
I suppose, that the performance of the file explorer is directly dependent on the amount of network folders. Some of them are usually not online...
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