On C/C++ undefined behaviours

[retard]

Fri, 20 Aug 2010 17:37:18 -0400, Nick Sabalausky wrote:

> "retard" <re at tard.com.invalid> wrote in message
> news:i4mrss$cam$1 at digitalmars.com...
>> Fri, 20 Aug 2010 19:04:41 +0200, Andrej Mitrovic wrote:
>>
>>> What are these Java programs for the desktop that run fast? I haven't
>>> encountered any, but maybe that's just because I didn't try them all
>>> out. Eclipse takes at least 20 seconds to load on startup on my quad
>>> core, that's not very fast. On the other hand, CodeBlocks which is
>>> coded in C++ and has  a few dozen plugins installed runs in an
>>> instant.
>>
>> Now that's a fair comparison! "Crysis runs so slowly but a hello world
>> written in Go is SO fast. This must prove that Go is much faster than
>> C+ +!"
>>
>> I think CodeBlocks is one of the most lightweight IDEs out there. Does
>> it even have full semantic autocompletion? Eclipse, on the other hand,
>> comes with almost everything you can imagine. If you turn off the
>> syntax check, Eclipse works just as fast as any native application on a
>> modern desktop.
> 
> I've tried eclipse with the fancy stuff off, and it's still slower than
> C::B or PN2 for me.

Of course it is. You're comparing apples and oranges. The core of Eclipse 
is much more customizable. I haven't used C::B lately, but does it even 
have a plugin updater functionality yet? If you want a fair comparison, 
write the _same_ application in Java and in some other language. E.g. 
jEdit is probably a bit faster with all plugins turned off.

When comparing, you also need to understand how the JIT compiler works. 
Using the Sun server VM, you need to visit each menu and use each visual 
component a few times to make the VM recompile the code. After few hours 
of use everything should run as fast as it can. Upgrading the JVM might 
also help because there are more JIT optimizations available.