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Date: Tue, 29 Apr 2025 23:56:04 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Cristian Prundeanu <cpru@amazon.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>,
	Hazem Mohamed Abuelfotoh <abuehaze@amazon.com>,
	Ali Saidi <alisaidi@amazon.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Geoff Blake <blakgeof@amazon.com>, Csaba Csoma <csabac@amazon.com>,
	Bjoern Doebel <doebel@amazon.com>,
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	Ingo Molnar <mingo@redhat.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
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	linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-tip-commits@vger.kernel.org, x86@kernel.org
Subject: Re: EEVDF regression still exists
Message-ID: <20250429215604.GE4439@noisy.programming.kicks-ass.net>
References: <20250429213817.65651-1-cpru@amazon.com>
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In-Reply-To: <20250429213817.65651-1-cpru@amazon.com>

On Tue, Apr 29, 2025 at 04:38:17PM -0500, Cristian Prundeanu wrote:
> Peter,
> 
> Here are the latest results for the EEVDF impact on database workloads. 
> The regression introduced in kernel 6.6 still persists and doesn't look 
> like it is improving.

Well, I was under the impression it had actually been solved :-(

My understanding from the last round was that Prateek and co had it
sorted -- with the caveat being that you had to stick SCHED_BATCH in at
the right place in MySQL start scripts or somesuch.

Prateek, Gautham?