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Date: Mon, 18 Mar 2024 16:40:33 +0000
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Subject: Re: [RFC PATCH 2/2] cpufreq/schedutil: Remove iowait boost
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To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org,
 juri.lelli@redhat.com, mingo@redhat.com, dietmar.eggemann@arm.com,
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References: <20240304201625.100619-1-christian.loehle@arm.com>
 <20240304201625.100619-3-christian.loehle@arm.com>
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From: Christian Loehle <christian.loehle@arm.com>
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On 18/03/2024 14:07, Rafael J. Wysocki wrote:
> On Mon, Mar 4, 2024 at 9:17 PM Christian Loehle
> <christian.loehle@arm.com> wrote:
>>
>> The previous commit provides a new cpu_util_cfs_boost_io interface for
>> schedutil which uses the io boosted utilization of the per-task
>> tracking strategy. Schedutil iowait boosting is therefore no longer
>> necessary so remove it.
> 
> I'm wondering about the cases when schedutil is used without EAS.
> 
> Are they still going to be handled as before after this change?

Well they should still get boosted (under the new conditions) and according
to my tests that does work. Anything in particular you're worried about?

So in terms of throughput I see similar results with EAS and CAS+sugov.
I'm happy including numbers in the cover letter for future versions, too.
So far my intuition was that nobody would care enough to include them
(as long as it generally still works).

Kind Regards,
Christian