From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C261B35A39F for ; Mon, 31 Aug 2026 17:09:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788196187; cv=none; b=ewIGViogUF+SnbhS5MZLYBRNiaVuCxvrxzV0Ni+6+8XWegsTxAIkjOcPbKcHGznYX1ICiXdkFCapEuIFUwCXSe88xv3lxsYtc4d+OmC48Zk0uWyyqDEhnRktBHKJ/jOcUoe3waMHu6rKD+PQ9ynKTQd+71UW6bl7mZ43s3xBt5s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788196187; c=relaxed/simple; bh=AlpzePPV9+6z39ry0lB5XfFqxLPzpfEHJT/XGwJwcXU=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=tqYzNtxudqB2BPCDxD1J2pIppQvnB/2yvWFqgEfAJbDMUoA2rVVrvPgTdmLscPs8s/9jwxEnBB1nGU3vyyOsFvmqqn9zRpnTZbkGJqc7mUS4pBrP/Fatb141EpRRaIDpZRpICRZ7bi00QI6C9j56jYFvDGCvhj6I9W8+AArcf7g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=03JWdFRt; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="03JWdFRt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 131FF1F000E9; Mon, 31 Aug 2026 17:09:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1788196185; bh=qJesAYSTVzpoXg/9Zj9W4p7RBJ2PVwQ/TQe4n2On7M0=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=03JWdFRtvhR6VDV6l0PUGA1DVunpqddI6VSWXI7dNneFUwRvZ3V6Dx7U6aGRkK3M7 PLcfwDkv+py26b0n8Lj5Y0GA2w1/IcEx6iHOlg7lrm7IlsnrZ1AEovAIcVX0coIofm Wj8rKpOXWwJABIA1jG+/4VHCfqVr+8y0MsMXWmI8= Date: Mon, 31 Aug 2026 10:09:44 -0700 From: Andrew Morton To: "Lorenzo Stoakes (ARM)" Cc: Taha Sezer , david@kernel.org, vbabka@kernel.org, mhocko@suse.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: vmpressure: scale window size based on machine memory Message-Id: <20260831100944.ccb2a8fe3b036ff7a258820a@linux-foundation.org> In-Reply-To: References: <20260831130316.448-1-tahasezer.is@gmail.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 31 Aug 2026 14:27:32 +0100 "Lorenzo Stoakes (ARM)" wrote: > I do have to ask if you're using an LLM here? If so, it isn't a very good one ;) I asked Gemini to write a reproducer for the Sashiko report (https://sashiko.dev/#/patchset/20260831130316.448-1-tahasezer.is@gmail.com) and Gemini told me : You spotted a severe mathematical regression in that commit. Your : analysis is entirely correct: the patch actually shrinks the : vmpressure window size for almost every machine on Earth (up to 8 TB : of RAM), doing the exact opposite of its stated goal. : [much more]