From: Greg KH <gregkh@linuxfoundation.org>
To: Paul Hedderly <paul@mjr.org>
Cc: WireGuard mailing list <wireguard@lists.zx2c4.com>
Subject: Re: Kernel lockup with (debian) 4.16.0-2-rt-amd64
Date: Wed, 13 Jun 2018 17:08:13 +0200 [thread overview]
Message-ID: <20180613150813.GA7789@kroah.com> (raw)
In-Reply-To: <98f37803e752f4d4f19b9064240f0b876b2db588.camel@mjr.org>
On Wed, Jun 13, 2018 at 03:54:24PM +0100, Paul Hedderly wrote:
> On Wed, 2018-06-13 at 15:52 +0200, Jason A. Donenfeld wrote:
> > Hi Paul,
> >
> > I got an -rt kernel up and running, enabled a bunch of nice debugging
> > options, and found a handful of problems, all of which were fixed by:
> > https://git.zx2c4.com/WireGuard/commit/?id=0f05452d043d8d047cf5d7987f
> > c2732b97d676e6
> >
> > I realize the solution in that patch is a bit of a bummer, but at the
> > very least it keeps things from breaking now. I'll see if I can
> > improve it somewhere down the line.
>
> OUch. "So on sane kernels" I guess RT isn't sane then!
>
> Yea that performance hit is a nuisance, although in reality when I
> really need RT I wont be doing much over a VPN... so I may have to suck
> up to rebooting between kernels for a while. No big deal.
Note, the -rt kernels _always_ run slower than a non-rt kernel. Real
time is not "faster", it is only "deterministic". And it achieves this
goal at the expense of performance, which is the only way it can be
done.
So I recommend just trying the "normal" kernel instead, odds are it will
work just fine for you, unless you have some _very_ specific max-bound
latency issues.
thanks,
greg k-h
next prev parent reply other threads:[~2018-06-13 15:04 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-12 20:00 Paul Hedderly
2018-06-12 21:35 ` Jason A. Donenfeld
2018-06-12 21:42 ` Paul Hedderly
2018-06-12 21:47 ` Jason A. Donenfeld
2018-06-13 1:58 ` Jason A. Donenfeld
2018-06-13 7:58 ` Paul Hedderly
2018-06-13 12:13 ` Jason A. Donenfeld
2018-06-13 13:52 ` Jason A. Donenfeld
2018-06-13 14:54 ` Paul Hedderly
2018-06-13 15:08 ` Greg KH [this message]
2018-06-13 16:07 ` Paul Hedderly
2018-06-13 21:12 ` Jason A. Donenfeld
2018-06-14 19:49 ` Paul Hedderly
2018-06-15 17:04 ` Jason A. Donenfeld
2018-06-13 14:49 ` Paul Hedderly
2018-06-12 21:38 ` Paul Hedderly
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