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From: "Pavel Klinkovský" <pavel.klinkovsky@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] Maximal number of processes
Date: Fri, 10 Jan 2014 15:24:30 +0100	[thread overview]
Message-ID: <CAGNd-2P61Fw0MjVSyM3X02BP=QKO+u_SJkyMUUbEORY411M8ew@mail.gmail.com> (raw)
In-Reply-To: <377f011e7a1ee2d06d0c80725a918a08@brasstown.quanstro.net>


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I discovered another interesting feature in my tests:

If 'fork' exceeds nproc value, kernel panics.
If 'fork' reaches the available memory limit, it is blocked until some
memory is released (e.g. by the finish of some process).

Pavel



2014/1/10 erik quanstrom <quanstro@quanstro.net>

> > launching 32000 processes was not possible.  the kernel got stuck.
>
> sloppy statement.  it's not clear if the kernel was really stuck or just
> hit something exponential.
>
> > here's one thing that's not immediately obvious, even when running the
> > kernel.  conv.nmach must be less than 0x7fffffff/(1000*1000) = 2147
> > to prevent reprioritize from doing silly things:
> >
> >       /*
> >        *  fairshare = 1.000 * conf.nproc * 1.000/load,
> >        * except the decimal point is moved three places
> >        * on both load and fairshare.
> >        */
> >       fairshare = (conf.nmach*1000*1000)/load;
>
> and, look.  the comment's wrong.  never read the comments!
>
> - erik
>
>

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      reply	other threads:[~2014-01-10 14:24 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-08  8:28 Pavel Klinkovský
2014-01-08 10:15 ` erik quanstrom
2014-01-08 15:23 ` Steven Stallion
2014-01-08 16:55   ` erik quanstrom
2014-01-09  8:08   ` Pavel Klinkovský
2014-01-09  9:45     ` Bruce Ellis
2014-01-09 16:36       ` Pavel Klinkovský
2014-01-10  9:11     ` Charles Forsyth
2014-01-10  9:15       ` Charles Forsyth
2014-01-10  9:38         ` Bruce Ellis
2014-01-10 13:48         ` erik quanstrom
2014-01-10 14:00           ` erik quanstrom
2014-01-10 14:24             ` Pavel Klinkovský [this message]

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