From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Weimer <fw-d32yF4oPJVt0XxTmqZlbVQ@public.gmane.org>
Subject: Re: [RFC PATCH] proc, pidns: Add highpid
Date: Sun, 30 Nov 2014 09:47:50 +0100
Message-ID: <87k32d13d5.fsf@mid.deneb.enyo.de>
References: <b0f6c4df0e8ef8afcc7b786edecb4be8c752941e.1417215468.git.luto@amacapital.net>
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	(Andy Lutomirski's message of "Fri, 28 Nov 2014 15:05:01 -0800")
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Cc: David Herrmann <dh.herrmann-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, systemd Mailing List <systemd-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org>, criu-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org, Pavel Emelyanov <xemul-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org>, Cyrill Gorcunov <gorcunov-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org>
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* Andy Lutomirski:

> The initial implementation is straightforward: highpid is simply a
> 64-bit counter. If a high-end system can fork every 3 ns (which
> would be amazing, given that just allocating a pid requires at
> atomic operation), it would take well over 1000 years for highpid to
> wrap.

I'm not sure if I'm reading the patch correctly, but is the counter
namespaced?  If yes, why?

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From: Florian Weimer <fw@deneb.enyo.de>
To: Andy Lutomirski <luto@amacapital.net>
Cc: David Herrmann <dh.herrmann@gmail.com>, linux-api@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        systemd Mailing List <systemd-devel@lists.freedesktop.org>,
        criu@openvz.org, Pavel Emelyanov <xemul@parallels.com>,
        Cyrill Gorcunov <gorcunov@openvz.org>
Subject: Re: [RFC PATCH] proc, pidns: Add highpid
References: <b0f6c4df0e8ef8afcc7b786edecb4be8c752941e.1417215468.git.luto@amacapital.net>
Date: Sun, 30 Nov 2014 09:47:50 +0100
In-Reply-To: <b0f6c4df0e8ef8afcc7b786edecb4be8c752941e.1417215468.git.luto@amacapital.net>
	(Andy Lutomirski's message of "Fri, 28 Nov 2014 15:05:01 -0800")
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* Andy Lutomirski:

> The initial implementation is straightforward: highpid is simply a
> 64-bit counter. If a high-end system can fork every 3 ns (which
> would be amazing, given that just allocating a pid requires at
> atomic operation), it would take well over 1000 years for highpid to
> wrap.

I'm not sure if I'm reading the patch correctly, but is the counter
namespaced?  If yes, why?