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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prev parent 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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