From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH v7 1/4] spinlock: A new lockref structure for lockless
 update of refcount
Date: Wed, 4 Sep 2013 14:34:05 -0700
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Cc: Ingo Molnar <mingo@kernel.org>, Al Viro <viro@zeniv.linux.org.uk>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Jeff Layton <jlayton@redhat.com>,
	Miklos Szeredi <mszeredi@suse.cz>,
	Ingo Molnar <mingo@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Andi Kleen <andi@firstfloor.org>,
	"Chandramouleeswaran, Aswin" <aswin@hp.com>,
	"Norton, Scott J" <scott.norton@hp.com>
To: Waiman Long <waiman.long@hp.com>
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On Wed, Sep 4, 2013 at 12:25 PM, Waiman Long <waiman.long@hp.com> wrote:
>
> Yes, the perf profile was taking from an 80-core machine. There isn't any
> scalability issue hiding for the short workload on an 80-core machine.
>
> However, I am certain that more may pop up when running in an even larger
> machine like the prototype 240-core machine that our team has been testing
> on.

Sure. Please let us know, I think it's going to be interesting to see
what that shows.

SGI certainly did much larger machines, but their primary target
tended to be all user space, so they had things like "tons of
concurrent page faults in the same process" rather than filename
lookup or the tty layer.

                Linus