[dpdk-dev] [PATCH 0/4] Extend --lcores to run on cores >RTE_MAX_LCORE

[Morten Brørup]

> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of David Marchand
> Sent: Tuesday, January 14, 2020 1:59 PM
> 
> On Mon, Dec 2, 2019 at 4:36 PM David Marchand
> <david.marchand at redhat.com> wrote:
> >
> > We are currently stuck with no option but recompile a DPDK if the
> system
> > has more cores than RTE_MAX_LCORE.
> > A bit of a pity when you get a system with more than 200+ cores and
> your
> > testpmd has been built and packaged with RTE_MAX_LCORE == 128.
> >
> > The --lcores does not need to care about the underlying cores, remove
> > this limitation.
> 
> Any comment?
> Thanks.
> 
> 
> --
> David Marchand
> 

I haven't reviewed the patch, but recall that the Mempool library sets up caches per lcore using hardcoded loops going from 0 to RTE_MAX_LCORE, regardless how many lcores are present and assigned to DPDK.

Making rte_max_lcore dynamic (and possibly auto-detected by the EAL) instead of defined at compile time might also be an improvement for systems with fewer cores than RTE_MAX_LCORE. But there are probably a lot of considerations regarding multi-process applications.


Med venlig hilsen / kind regards
- Morten Brørup