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Date:   Thu, 20 Sep 2018 21:45:10 +0300
From:   Cyrill Gorcunov <gorcunov@gmail.com>
To:     Dmitry Safonov <dima@arista.com>
Cc:     linux-kernel@vger.kernel.org,
        Dmitry Safonov <0x7f454c46@gmail.com>,
        Andrei Vagin <avagin@openvz.org>,
        Adrian Reber <adrian@lisas.de>,
        Andy Lutomirski <luto@kernel.org>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
        Jeff Dike <jdike@addtoit.com>, Oleg Nesterov <oleg@redhat.com>,
        Pavel Emelyanov <xemul@virtuozzo.com>,
        Shuah Khan <shuah@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        containers@lists.linux-foundation.org, criu@openvz.org,
        linux-api@vger.kernel.org, x86@kernel.org
Subject: Re: [RFC 02/20] timens: Add timens_offsets
Message-ID: <20180920184510.GC20786@uranus>
References: <20180919205037.9574-1-dima@arista.com>
 <20180919205037.9574-3-dima@arista.com>
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On Wed, Sep 19, 2018 at 09:50:19PM +0100, Dmitry Safonov wrote:
> From: Andrei Vagin <avagin@openvz.org>
> 
> Introduce offsets for time namespace. They will contain adjustment
> needed to convert clocks to/from host's.
> 
> Allocate one page for each time namespace that will be premapped into
> userspace with vvar pages.

Is not it too much?! The whole page per each clone(new-time-ns) call.
Moreover everytime it is get explicitly zeroifyed. Don't get me wrong,
maybe I miss something obvious, but additional 4K per process, guys :)