[fpc-pascal] Heavy heap fragmentation issue

Burkhard Carstens fpc at bcsoft.de
Sat Jul 13 08:36:36 CEST 2019

Am Dienstag, 4. Juni 2019 18:00 schrieb Martok:
> Am 03.06.2019 um 14:49 schrieb Marco van de Voort:
> > Note that it is fairly typical that also frustrated pre fastmm D7.
> > Back then I wrote a simple pool-factory combo class for it, and
> > with D2009 I upgraded it to generics,so that I can easily create
> > pools for many such objects.
> Well, there is a general-purpose pooled allocator already. It's
> called the heap manager ;-)
> Jokes aside, I did a bunch of counting. The only thing that sticks
> around are 50kB TLazIntfImage instances. Everything else gets freed
> right after processing. Just from the order of alloc/frees, there
> shouldn't even be gaps, so I would expect the next iteration to just
> find those allocations to be empty and reuse them. But for some
> reason, that doesn't happen.
> I've compiled with FastMM for now, but it turns out this is in fact a
> bit slower than the RTL MM, and I don't really trust my port yet...

Try compiling the heap manager with "-dBESTMATCH". This makes it a bit 
slower but greatly reduces fragmentation.

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