On Wed, Sep 13, 2017 at 15:58:11 +0200, Joerg Sonnenberger wrote: > On Wed, Sep 13, 2017 at 04:48:54PM +0300, Valery Ushakov wrote: > > On a typical cpu that would be the alignment of "long double" I guess. > > (I haven't checked, but it looks like that's what TINY_MIN_2POW > > ensures for "tiny" allocation). > > Vector registers require 128 or even 256bit alignment. We have like most > systems for a long time been guaranteeing 16 Bytes alignment.
BTW, jemalloc.c has: #ifdef __arm__ # define QUANTUM_2POW_MIN 3 ... Which implies, I gather, that on arm it's only 8 bytes, right? Anyway, I'd still say that explicit posix_memalign() is better than silent assumption. (Not C99 aligned_alloc() though, as it imposes the restriction that size is a multiple of alignment). -uwe
