[fpc-devel] Compiler bottlenecks]

[Florian Klaempfl]

Hans-Peter Diettrich schrieb:
> Thaddy schrieb:
>> Hans-Peter Diettrich wrote:
>>>
>>> Memory management can not normally be parallelized.
>>>
>> What's this then: http://topsoftwaresite.nl/ You are talking cows dung.
>> It is actually in production at one of the largest stockbrokers in
>> Europe.
>> You should have written : "It is hard to do parallization"
> 
> My point is: when multiple threads try to acquire an new memory block at
> the same time, and they happen to find the same gap, then only one of
> these can win. The other threads must continue or - in the worst case -
> restart their search for the next matching gap.
> 
> So IMO only a low *chance* for such concurrent tries can result in
> *typically* better performance of such a memory management model. With
> increasing memory fragmentation the collision chance increases as well.

Just look at the FPC memory manager: to avoid this some structures like
the freelist are thread specific.