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From: Bo Persson <bo@bo-persson.se>
Newsgroups: comp.lang.c++
Subject: Re: Examples of current platforms/architectures where sizeof(void*) > sizeof(int*) ?
Date: Wed, 1 Sep 2021 10:44:59 +0200
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On 2021-09-01 at 10:13, Bonita Montero wrote:
> Am 01.09.2021 um 09:57 schrieb Bo Persson:
> 
>> Even on current byte addressed machines, malloc(1) gets us 8- or 
>> 16-bytes aligned allocations, partly to reduce memory fragmentation.
> 
> No, just to limit the number of size-pools.

And why do they have memory pools?  :-)

Note that I said "partly". Another reason is that some pool allocators 
use the space of the freed memory block to administer the pool. Then 
there is a 1-2 pointer minimum size for a block.

> With modern allocators like jemallic, mimalloc or tcmalloc, fragmen-
> tation isn't an issue for the small size pools and on 64 bit machines
> isn't an issue for medium size pools (large blocks are usually directly
> allocated via mmap() e.g.).