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Subject: Re: [patch V2 00/20] timer: Refactor the timer wheel
From: Rik van Riel <riel@redhat.com>
To: Thomas Gleixner <tglx@linutronix.de>, Eric Dumazet <edumazet@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>,
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        Linus Torvalds <torvalds@linux-foundation.org>,
        George Spelvin <linux@sciencehorizons.net>,
        Len Brown <lenb@kernel.org>
Date: Mon, 20 Jun 2016 15:03:57 -0400
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On Mon, 2016-06-20 at 15:56 +0200, Thomas Gleixner wrote:
>=C2=A0
> 2) Cut off at 37hrs for HZ=3D1000. We could make this configurable as a
> 1000HZ
> =C2=A0=C2=A0 option so datacenter folks can use this and people who don't=
 care
> and want
> =C2=A0=C2=A0 better batching for power can use the 4ms thingy.
>=20

It might be easy enough to simply re-queue a timer that
has not expired yet after 37 hours.

How many 37 hour timers will there be outstanding at any
one time, that expire around the same time?

Chances are, not many at all. In fact, the vast majority
of them are likely to be deleted long before they ever
expire.

Timers lasting longer than 37 hours do not seem like
something worth optimizing for.

--=20
All Rights Reversed.


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