Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 7 Nov 2015 22:51:14 +1100 (EST)
From:      Bruce Evans <brde@optusnet.com.au>
To:        Hans Petter Selasky <hps@selasky.org>
Cc:        Bruce Evans <brde@optusnet.com.au>, Rasool Al-Saadi <ralsaadi@swin.edu.au>, Luigi Rizzo <rizzo@iet.unipi.it>,  "freebsd-net@freebsd.org" <freebsd-net@freebsd.org>
Subject:   Re: Timing issue with Dummynet on high kernel timer interrupt
Message-ID:  <20151107223816.D1837@besplex.bde.org>
In-Reply-To: <563DD6B2.8010607@selasky.org>
References:  <6545444AE21C2749939E637E56594CEA3C0DCCC4@gsp-ex02.ds.swin.edu.au> <5638B7B5.3030802@selasky.org> <6545444AE21C2749939E637E56594CEA3C0DE7FF@gsp-ex02.ds.swin.edu.au> <563B2703.5080402@selasky.org> <6545444AE21C2749939E637E56594CEA3C0E0BD9@gsp-ex02.ds.swin.edu.au> <563C6864.2090907@selasky.org> <CA%2BhQ2%2Bhm2z0MkB-8w5xJM7%2Biz13r_ZjwmpZBnb30_D_48gaf-w@mail.gmail.com> <563C786C.1050305@selasky.org> <CA%2BhQ2%2Bj0WiGgzV119M1ZQiXP5Z7fq7deVxDPkOhvTc7hpTETKw@mail.gmail.com> <563CC186.9000807@selasky.org> <6545444AE21C2749939E637E56594CEA3C0E1B79@gsp-ex02.ds.swin.edu.au> <20151107162915.A893@besplex.bde.org> <563DD6B2.8010607@selasky.org>

next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, 7 Nov 2015, Hans Petter Selasky wrote:

> On 11/07/15 07:19, Bruce Evans wrote:
>> I don't know if CTLFLAG_RWTUN with SYSCTL_PROC() actually works for all
>> types, but it is used with CTLFLAG_STRING for kern.corefile.  This is
>> another bogus undocumented tunable.  It is better documented as a sysctl
>> than most since it is old so it is documented in sysctl(8).  It is not
>> documented as a tunable there of course.  It is also not documented as
>> a tunable in core(5).
>
> SYSCTL_PROC() works with RWTUN from /boot/loader.conf, as long as the 
> procedure callback handles early calls during boot.

Hmm, that would be messy if it wants to do hardware stuff like
sysctl_kern_eventtimer_periodic() does.

Timercounters only have 1 MI tunable
(sysctl_kern_timecounter_adjprecision).  It has a (cold) check to avoid
doing too much.

Bruce



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20151107223816.D1837>