On Sat, 2 Mar 2024 14:05:45 +0100
Morten Brørup <m...@smartsharesystems.com> wrote:
> >
> > > My experience with replacing rte_memcpy() with memcpy() (or vice
> > versa)
> > > is mixed.
> > >
> > > I've also tried just dropping the DPDK-custom memcpy() implementation
> > > altogether, and that caused a performance drop (in a particular app,
> > on
> > > a particular compiler and CPU).
>
> I guess the compilers are just not where we want them to be yet.
>
> I don't mind generally replacing rte_memcpy() with memcpy() in the control
> plane.
> But we should use whatever is more efficient in the data plane.
>
> We must also keep in mind that DPDK supports old distros with old compilers.
> We should not remove a superfluous hand crafted optimization if a supported
> old compiler hasn't caught up with it yet, i.e. if it isn't superfluous on
> some of the old compilers supported by DPDK.
When I scanned the result.
1. Most copies were small (like Ether address or IPv6 address) and
compiler
inlining should beat a function call every time.
2. Larger structure copies were in control path.
