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Date: Tue, 28 Nov 2017 13:53:16 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Giuseppe Scrivano <gscrivan@redhat.com>
Cc: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org,
        mingo@kernel.org, dave@stgolabs.net
Subject: Re: [RFC PATCH] ipc, mqueue: lazy call kern_mount_data in new
 namespaces
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On Mon, 27 Nov 2017 13:55:50 +0100 Giuseppe Scrivano <gscrivan@redhat.com> wrote:

> kern_mount_data is a relatively expensive operation when creating a
> new IPC namespace, so delay the mount until its first usage when not
> creating the the global namespace.
> 
> On my machine, the time for creating 1000 new IPC namespaces dropped
> from ~8s to ~2s.

OK, but this simply moves the expense so it happens later on.  Why is
that better?