From: Antonio Di Bacco <a.dibacco.ks@gmail.com>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: users@dpdk.org
Subject: Re: Large interruptions for EAL thread running on isol core
Date: Fri, 24 Jun 2022 11:45:20 +0200 [thread overview]
Message-ID: <CAO8pfFn8wYs-w=FSH3Xk7+ZRMvxaeHXz12Fow0cFHB-0FHkMpg@mail.gmail.com> (raw)
In-Reply-To: <20220623114159.0fb198b3@hermes.local>
Thank you, didn't know that "System management units" could steal
CPU!!! That is scary
On Thu, Jun 23, 2022 at 8:42 PM Stephen Hemminger
<stephen@networkplumber.org> wrote:
>
> On Thu, 23 Jun 2022 20:03:02 +0200
> Antonio Di Bacco <a.dibacco.ks@gmail.com> wrote:
>
> > I'm running a DPDK thread on an isolated core. I also set some flags
> > that could help keeping the core at rest on linux like: nosoftlockup
> > nohz_full rcu_nocbs irqaffinity.
> >
> > Unfortunately the thread gets some interruptions that stop the thread
> > for about 20-30 micro seconds. This seems smal but my application
> > suffers a lot.
> >
> > I also tried to use rte_thread_set_priority that indeed has a strong
> > effect but unfortunately creates problems to Linux (like network not
> > working).
> >
> > Is there any other knob that could help running the DPDK thread with
> > minimum or no interruptions at all?
>
> Look with perf and see what is happening.
> First check for interrupt affinity.
> Don't try real time priority.
>
> The other thing to look for would be any BIOS settings.
> Some system management units can take away CPU silently for polling
> some internal housekeeping.
next prev parent reply other threads:[~2022-06-24 9:45 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-23 18:03 Antonio Di Bacco
2022-06-23 18:07 ` Omer Yamac
2022-06-24 9:43 ` Antonio Di Bacco
2022-06-23 18:41 ` Stephen Hemminger
2022-06-24 9:45 ` Antonio Di Bacco [this message]
2022-06-24 10:43 ` Kinsella, Ray
2022-06-23 19:03 ` Carsten Andrich
2022-06-24 15:01 ` Stephen Hemminger
2022-06-24 15:41 ` Carsten Andrich
2022-06-24 16:42 ` Stephen Hemminger
2022-06-28 7:25 ` Carsten Andrich
2022-06-28 15:19 ` Stephen Hemminger
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