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From: Florian Weimer <fweimer@redhat.com>
To: Torvald Riegel <triegel@redhat.com>
Cc: Carlos O'Donell <carlos@redhat.com>,  "H.J. Lu" <hjl.tools@gmail.com>,  Szabolcs Nagy <Szabolcs.Nagy@arm.com>,  libc-alpha <libc-alpha@sourceware.org>
Subject: Re: [PATCH] NUMA spinlock [BZ #23962]
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Date: Tue, 15 Jan 2019 12:17:00 -0000
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	(Torvald Riegel's message of "Tue, 15 Jan 2019 13:01:49 +0100")
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* Torvald Riegel:

> What I mean is that applications would have to want to use locks provided
> by tbb, whether those are locks/mutexes that exist in tbb today or a new
> API that would be added.
>
> Put differently, I'm not optimistic about tbb being a good way to get
> feedback.

Do you want to run existing workloads with a new mutex implementation?

Then we can't add new flags or change ABI in any way and would have to
use a tunable.  And to get feedback, we would have to make the new
implementation the default, with a tunable to get back the old
implementation.

Thanks,
Florian