[fpc-devel] Performance of string handling in trunk

[luiz americo pereira camara]

2013/6/20 Sergei Gorelkin <sergei_gorelkin at mail.ru>:
> 20.06.2013 16:15, luiz americo pereira camara пишет:
>
>> I looked at
>> http://forum.lazarus.freepascal.org/index.php/topic,21223.0.html
>>
>> There's a significant performance drop in fpc trunk
>>
>> Is there anything wrong or this is the expected result?
>>
> Some slowdown is of course the expected result: it is impossible to add all
> codepage stuff without performance impact. Even though conversions happen
> only when codepages differ, the code which checks the codepages is executed
> anyway on every operation.

I know that.

The point is that i would expect a smaller performance hit when
there's no conversion going on. Something between 10% slower. In the
cited case is more than 50% slow.

> The question is, which part of observed slowdown
> is unavoidable and which can be eliminated by more accurate implementation.

Maybe in that example there's going an (unneeded) conversion?

Luiz