Performance of exception handling

[Denis Koroskin]

On Tue, 26 Apr 2011 16:43:26 +0400, Alexander <aldem+dmars at nk7.net> wrote:

> On 26.04.2011 12:57, Vladimir Panteleev wrote:
>
>> On my Windows box with an i7 920, a simple try/throw/catch loop runs at  
>> about 130000 iterations per second.
>
>   Well, g++ with same loop on same linux system gives ca. 160000 iter/s,  
> which is quite OK for me.
>
>> Perhaps DMD doesn't use SEH on Linux, and instead uses setjmp/longjmp?
>
>   I've not found any references to setjmp/longjmp, but what I've found -  
> disabling trace
>   handler with "Runtime.traceHandler = null" boost performance  
> significantly - in my case
>   I got 1600000 iter/s (wow!), which is perfectly OK.
>
>   AFAIK, traceHandler is something that prints out the stack trace,  
> providing valuable
>   information only when there is no catch. If there is a catch, then,  
> obviously,
>   this slows down exception processing significantly without any need  
> (it is called
>   on every invocation of throw).
>
>   I am right?
>
> /Alexander

Full stack trace resolving could be done lazily, but you need to save call  
stack addresses at throw side (which is very quick anyway).

Could you please file a bugzilla enhancement request for that?