[fpc-devel] FPC/Lazarus Rebuild performance

[Jonas Maebe]

On 12 Sep 2010, at 10:43, Marco van de Voort wrote:

> I'm no expert on profiling the compiler, but if I read the various threads
> over the years I see defensive and conflicting statements:
> 
> In discussions with Hans, it is said that I/O is not a factor, since after
> one run everything is cached anyway, and then in this thread I/O is to blame
> for a huge difference in speed.

Disk throughput doesn't really matter. Reading directory contents, getting file information and opening/closing files is another matter.

> The same with the fact that we use shortstring for performance in many
> places where delphi in fact allows longer mangled names and is faster.

That's a non sequitur.

> - Possibily, a defaultly installed windows searches through a larger unit
>  path (more dirs, more file) than Delphi _default_

I've also been thinking that.

> - Most profiling recently afaik has been done by Jonas, and thus not
>  on Windows. Yet the delphi comparisons are on windows. 

There's a free profiler for Windows by AMD: http://developer.amd.com/cpu/codeanalyst/Pages/default.aspx


Jonas