From: tglx@linutronix.de (Thomas Gleixner)
Subject: [RFC 00/20] ns: Introduce Time Namespace
Date: Thu, 27 Sep 2018 23:41:49 +0200 (CEST) [thread overview]
Message-ID: <alpine.DEB.2.21.1809272335430.8118@nanos.tec.linutronix.de> (raw)
Message-ID: <20180927214149.tsD0_Kx13n_EuaS63exF7EV_Gt7WnQm0NmfdfaRI6YA@z> (raw)
In-Reply-To: <alpine.DEB.2.21.1809272247270.8118@nanos.tec.linutronix.de>
On Thu, 27 Sep 2018, Thomas Gleixner wrote:
> Add time skew via NTP/PTP into the picture and you might have to adjust
> timers as well, because you need to guarantee that they are not expiring
> early.
>
> I haven't looked through Dimitry's patches yet, but I don't see how this
> can work at all without introducing subtle issues all over the place.
And just a quick scan tells me that this is broken. Timers will expire
early or late. The latter is acceptible to some extent, but larger delays
might come with surprise. Expiring early is an absolute nono.
Thanks,
tglx
next prev parent reply other threads:[~2018-09-27 21:41 UTC|newest]
Thread overview: 78+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-19 20:50 [RFC 00/20] ns: Introduce Time Namespace dima
2018-09-19 20:50 ` Dmitry Safonov
2018-09-19 20:50 ` [RFC 16/20] selftest: Add Time Namespace test for supported clocks dima
2018-09-19 20:50 ` Dmitry Safonov
2018-09-24 21:36 ` shuah
2018-09-24 21:36 ` Shuah Khan
2018-09-19 20:50 ` [RFC 17/20] selftest/timens: Add test for timerfd dima
2018-09-19 20:50 ` Dmitry Safonov
2018-09-19 20:50 ` [RFC 18/20] selftest/timens: Add test for clock_nanosleep dima
2018-09-19 20:50 ` Dmitry Safonov
2018-09-19 20:50 ` [RFC 19/20] timens/selftest: Add procfs selftest dima
2018-09-19 20:50 ` Dmitry Safonov
2018-09-19 20:50 ` [RFC 20/20] timens/selftest: Add timer offsets test dima
2018-09-19 20:50 ` Dmitry Safonov
2018-09-21 12:27 ` [RFC 00/20] ns: Introduce Time Namespace ebiederm
2018-09-21 12:27 ` Eric W. Biederman
2018-09-24 20:51 ` avagin
2018-09-24 20:51 ` Andrey Vagin
2018-09-24 22:02 ` ebiederm
2018-09-24 22:02 ` Eric W. Biederman
2018-09-25 1:42 ` avagin
2018-09-25 1:42 ` Andrey Vagin
2018-09-26 17:36 ` ebiederm
2018-09-26 17:36 ` Eric W. Biederman
2018-09-26 17:59 ` 0x7f454c46
2018-09-26 17:59 ` Dmitry Safonov
2018-09-27 21:30 ` tglx
2018-09-27 21:30 ` Thomas Gleixner
2018-09-27 21:41 ` tglx [this message]
2018-09-27 21:41 ` Thomas Gleixner
2018-10-01 23:20 ` avagin
2018-10-01 23:20 ` Andrey Vagin
2018-10-02 6:15 ` tglx
2018-10-02 6:15 ` Thomas Gleixner
2018-10-02 21:05 ` 0x7f454c46
2018-10-02 21:05 ` Dmitry Safonov
2018-10-02 21:26 ` tglx
2018-10-02 21:26 ` Thomas Gleixner
2018-09-28 17:03 ` ebiederm
2018-09-28 17:03 ` Eric W. Biederman
2018-09-28 19:32 ` tglx
2018-09-28 19:32 ` Thomas Gleixner
2018-10-01 9:05 ` ebiederm
2018-10-01 9:05 ` Eric W. Biederman
2018-10-01 9:15 ` Setting monotonic time? ebiederm
2018-10-01 9:15 ` Eric W. Biederman
2018-10-01 18:52 ` tglx
2018-10-01 18:52 ` Thomas Gleixner
2018-10-02 20:00 ` arnd
2018-10-02 20:00 ` Arnd Bergmann
2018-10-02 20:06 ` tglx
2018-10-02 20:06 ` Thomas Gleixner
2018-10-03 4:50 ` ebiederm
2018-10-03 4:50 ` Eric W. Biederman
2018-10-03 5:25 ` tglx
2018-10-03 5:25 ` Thomas Gleixner
2018-10-03 6:14 ` ebiederm
2018-10-03 6:14 ` Eric W. Biederman
2018-10-03 7:02 ` arnd
2018-10-03 7:02 ` Arnd Bergmann
2018-10-03 6:14 ` tglx
2018-10-03 6:14 ` Thomas Gleixner
2018-10-01 20:51 ` avagin
2018-10-01 20:51 ` Andrey Vagin
2018-10-02 6:16 ` tglx
2018-10-02 6:16 ` Thomas Gleixner
2018-10-21 1:41 ` [RFC 00/20] ns: Introduce Time Namespace avagin
2018-10-21 1:41 ` Andrei Vagin
2018-10-21 3:54 ` avagin
2018-10-21 3:54 ` Andrei Vagin
2018-10-29 20:33 ` tglx
2018-10-29 20:33 ` Thomas Gleixner
2018-10-29 21:21 ` ebiederm
2018-10-29 21:21 ` Eric W. Biederman
2018-10-29 21:36 ` tglx
2018-10-29 21:36 ` Thomas Gleixner
2018-10-31 16:26 ` avagin
2018-10-31 16:26 ` Andrei Vagin
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