From: Thomas Monjalon <thomas@monjalon.net>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: "Morten Brørup" <mb@smartsharesystems.com>,
dev@dpdk.org, bruce.richardson@intel.com, dev@dpdk.org,
"David Marchand" <david.marchand@redhat.com>
Subject: Re: [PATCH v3 0/2] allow creating thread with real-time priority
Date: Thu, 26 Oct 2023 21:55:24 +0200 [thread overview]
Message-ID: <2655403.X9hSmTKtgW@thomas> (raw)
In-Reply-To: <20231026092840.71f0772b@hermes.local>
26/10/2023 18:28, Stephen Hemminger:
> On Thu, 26 Oct 2023 16:08:02 +0200
> Morten Brørup <mb@smartsharesystems.com> wrote:
>
> > > > In our recent tests, nanosleep() itself took around 50 us. So you need to
> > > sleep longer than that for your thread not to be runnable when the nanosleep()
> > > wakes up again, because 50 us has already passed in "nanosleep overhead".
> > > > 10 milliseconds provides plenty of margin, and corresponds to 10 jiffies on
> > > a 1000 Hz kernel. (I don't know if it makes any difference for the kernel
> > > scheduler if the timer crosses a jiffy border or not.)
> > >
> > > 10 ms looks like an eternity.
> >
> > Agree. It is only for functional testing, not for production!
>
> To be safe the sleep has to be longer than the system clock tick.
> Most systems are built today with HZ=250 but really should be using HZ=1000
> on modern CPU's.
If it has to be more than 1 ms,
we should mention it is a slow call
which may be skipped if the thread is already blocking on something else.
next prev parent reply other threads:[~2023-10-26 19:55 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-24 12:54 [PATCH] eal/unix: " Thomas Monjalon
2023-10-24 13:55 ` Morten Brørup
2023-10-24 16:04 ` Stephen Hemminger
2023-10-25 13:15 ` Thomas Monjalon
2023-10-25 13:34 ` Bruce Richardson
2023-10-25 13:44 ` Thomas Monjalon
2023-10-25 15:08 ` Stephen Hemminger
2023-10-25 15:14 ` Bruce Richardson
2023-10-25 15:18 ` Thomas Monjalon
2023-10-25 15:32 ` Thomas Monjalon
2023-10-25 15:13 ` [PATCH v2] " Thomas Monjalon
2023-10-25 15:37 ` Stephen Hemminger
2023-10-25 16:46 ` Thomas Monjalon
2023-10-25 17:54 ` Morten Brørup
2023-10-25 21:33 ` Stephen Hemminger
2023-10-26 7:33 ` Morten Brørup
2023-10-26 16:32 ` Stephen Hemminger
2023-10-26 17:07 ` Morten Brørup
2023-10-26 0:00 ` Stephen Hemminger
2023-10-25 16:31 ` [PATCH v3 0/2] " Thomas Monjalon
2023-10-25 16:31 ` [PATCH v3 1/2] eal: add thread yield functions Thomas Monjalon
2023-10-25 16:40 ` Bruce Richardson
2023-10-25 17:06 ` Thomas Monjalon
2023-10-25 18:07 ` Morten Brørup
2023-10-25 16:31 ` [PATCH v3 2/2] eal/unix: allow creating thread with real-time priority Thomas Monjalon
2023-10-26 13:36 ` [PATCH v3 0/2] " Thomas Monjalon
2023-10-26 13:44 ` Morten Brørup
2023-10-26 13:57 ` Morten Brørup
2023-10-26 14:04 ` Thomas Monjalon
2023-10-26 14:08 ` Morten Brørup
2023-10-26 14:30 ` Thomas Monjalon
2023-10-26 14:50 ` Morten Brørup
2023-10-26 14:59 ` Morten Brørup
2023-10-26 15:54 ` Bruce Richardson
2023-10-26 16:07 ` Thomas Monjalon
2023-10-26 16:50 ` Morten Brørup
2023-10-26 19:51 ` Thomas Monjalon
2023-10-27 7:19 ` Morten Brørup
2023-10-26 16:28 ` Stephen Hemminger
2023-10-26 19:55 ` Thomas Monjalon [this message]
2023-10-26 21:10 ` Stephen Hemminger
2023-10-26 14:10 ` David Marchand
2023-10-26 13:37 ` [PATCH v4 " Thomas Monjalon
2023-10-26 13:37 ` [PATCH v4 1/2] eal: add thread yield functions Thomas Monjalon
2023-10-26 13:37 ` [PATCH v4 2/2] eal/unix: allow creating thread with real-time priority Thomas Monjalon
2023-10-26 14:19 ` [PATCH v5 0/2] " Thomas Monjalon
2023-10-26 14:19 ` [PATCH v5 1/2] eal: add thread yield functions Thomas Monjalon
2023-10-26 14:19 ` [PATCH v5 2/2] eal/unix: allow creating thread with real-time priority Thomas Monjalon
2023-10-26 20:00 ` [PATCH v5 0/2] " Thomas Monjalon
2023-10-26 23:35 ` Tyler Retzlaff
2023-10-27 8:08 ` [PATCH v6 1/1] eal/unix: " Thomas Monjalon
2023-10-27 8:45 ` Morten Brørup
2023-10-27 9:11 ` Thomas Monjalon
2023-10-27 18:15 ` Stephen Hemminger
2024-10-07 19:27 ` Stephen Hemminger
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