Re: Shared memory between two primary DPDK processes

[Antonio Di Bacco <a.dibacco.ks@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 1511 bytes --]

Il giorno gio 14 apr 2022 alle ore 21:01 Dmitry Kozlyuk <
dmitry.kozliuk@gmail.com> ha scritto:

> 2022-04-14 10:20 (UTC+0200), Antonio Di Bacco:
> [...]
> > Ok, after having a look to memif I managed to exchange the fd  between
> the
> > two processes and it works.
> > Anyway the procedure seems a little bit clunky and I think I'm going to
> use
> > the new SYSCALL pidfd_getfd
> > to achieve the same result.  In your opinion this method (getfd_pidfd)
> > could also work if the two DPDK processes
> > are inside different docker containers?
>
> Honestly, I've just learned about pidfd_getfd() from you.
> But I know that containers use PID namespaces, so there's a question
> how you will obtain the pidfd of a process in another container.
>
> In general, any method of sharing FD will work.
> Remember that you also need offset and size.
> Given that some channel is required to share those,
> I think Unix domain socket is still the preferred way.
>
> > Or is there another mechanims like using handles to hugepages present in
> > the filesystem to share between two
> > different containers?
>
> FD is needed for mmap().
> You need to either pass the FD or open() the same hugepage file by path.
> I advise against using paths because they are not a part of DPDK API
> contract.
>

Thank you very much Dmitry, your answers are always enlightening.
I'm going to ask a different question on the dpdk.org about the best
practice to share memory between two dpdk processes running in different
containers.

[-- Attachment #2: Type: text/html, Size: 2007 bytes --]