From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B97C0E8FDC3 for ; Thu, 5 Oct 2023 09:46:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 138C78D00BA; Thu, 5 Oct 2023 05:46:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0E9178D00B4; Thu, 5 Oct 2023 05:46:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EF2E68D00BA; Thu, 5 Oct 2023 05:46:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id E0C498D00B4 for ; Thu, 5 Oct 2023 05:46:42 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id A49D8A03D6 for ; Thu, 5 Oct 2023 09:46:42 +0000 (UTC) X-FDA: 81310928244.11.E2939DB Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf04.hostedemail.com (Postfix) with ESMTP id 7CB7940016 for ; Thu, 5 Oct 2023 09:46:40 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf04.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1696499201; a=rsa-sha256; cv=none; b=JxPGxMkrZlV96hs9Yln4+WwQ4+jdlbXzVpX0RLDM233XARmXQ8FGwCZnZEg9crNU7sUvOB oYOGHTpgqZlX+jBbvEsE/SbTAgPkPr3u4sfypFB5CnlQBlNlVuno+UJyKKr314dO8TGqLn 1QNS3ojY+o1E4YHzrVki2OhTMzvXp88= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf04.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1696499201; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=q7YyX5zgfQkvzTwHQdyNlyv7jgUcWy/Bg19dA685Slc=; b=x5+SYNmX49IFg9SluNEihse5P5tyGZzow6KhS1shz1eVPGkEchwTDDplv+l5e4aOxAZJAs LZsmeN4L5Nlq3XQ8zTzV6E6BylngFHbOkI1PatCFWzZ9kmVUdPcBtkMiTWi0VCLEkdkHd7 MY6SMoDY7C3Z76zTozPj9oqJN3eebR8= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 01917152B; Thu, 5 Oct 2023 02:47:18 -0700 (PDT) Received: from [10.1.39.183] (XHFQ2J9959.cambridge.arm.com [10.1.39.183]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B36493F5A1; Thu, 5 Oct 2023 02:46:36 -0700 (PDT) Message-ID: <10061842-139b-4b65-8595-a09c55c000d3@arm.com> Date: Thu, 5 Oct 2023 10:46:35 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: ANON_LARGE_FOLIOS meeting follow-up & refined proposal Content-Language: en-GB To: David Hildenbrand , John Hubbard , Matthew Wilcox , Yang Shi , "Yin, Fengwei" , Yu Zhao , Zi Yan , David Rientjes , Andrew Morton , Vlastimil Babka , "Kirill A. Shutemov" , Hugh Dickins Cc: Linux-MM References: <4966f496-9f71-460c-b2ab-8661384ce626@arm.com> <4830fb3e-4a35-4842-98f4-9e7baa0e692a@arm.com> <7301771f-d654-4e5a-a197-3a3d8750440c@nvidia.com> <92937776-1e16-47e5-bef9-4c1a04bc98c0@arm.com> <5fa4aa95-6982-7879-e067-69fdb8b76d01@redhat.com> <1b03f4d6-634d-4786-81a0-5a104799b125@arm.com> <9d13a144-a36c-45d1-b7db-a08f84fa54ca@arm.com> From: Ryan Roberts In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 7CB7940016 X-Stat-Signature: ixtkxu37wfj6n394gajuka3i1ftd7hhs X-Rspam-User: X-HE-Tag: 1696499200-382543 X-HE-Meta: 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 6Pm2Xt4w 7MP2tlhXJmpDYwrb05KA5lnM6d9X1yUjkW8YDDVjNKoVFx86ORV+wOaL2IsyH7TJpv/MT5UhRseJ13ULYkeOEBvAYYOrndHxKu4wuI0rrM/UZdTOR4FaYYzthp1ZJMol54DWA1rN83vcPzklradHwwpnraTB4PTjFWexK4e6UXC7HAMI4NTmbl+NxLZ4l4KPAhiWd X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 05/10/2023 09:15, David Hildenbrand wrote: > On 05.10.23 09:37, Ryan Roberts wrote: >> On 02/10/2023 13:58, David Hildenbrand wrote: >>>> [...] >>>> >>>> My concern is that the "fresh start" is not as simple as it appears. I've come >>>> to the conclusion that if we have a new interface, then it should really be a >>>> strict superset of THP to make it extensible in future. But that opens >>>> questions >>> >>> ^ +1 >>> >>>> about how you configure PMD-sized allocations when both interfaces disagree. >>>> For >>>> "enabled" its fairly straightforward; you can do a logical OR. But its less >>>> clear how to handle disagreement over defrag. And then you have huge_zero_page >>>> and khugepaged etc, which might just stay with THP. But eventually we will >>> >>> Probably we want everything that THP had (khugepaged, zeropage, ...) also on >>> some (selected?) smaller orders. >>> >>>> probably want to do async collapse for smaller order folios too, and at that >>>> point you have to duplicate all those controls... So I concluded that actually >>>> it is cleaner to just bolt on a small-order extension to THP. I've updated all >>>> the docs, and that was pretty simple to do, which usually suggests that the >>>> extension is purely additive and shouldn't be confusing. >>> >>> Fine with me. I don't quite like bitmaps exposed to user space, though. Just >>> having a user-readable list or a "directory" with various options as files might >>> be cleaner ... >>> >>>> >>>> Take a look at the patches, then make a judgement ;-) >>>> >>> >>> ... but we'll discuss it there :) >>> >> >> David, FYI, the patches are posted at [1] (you're cc'ed) and have been in >> mm-unstable for nearly a week - so I guess they will go to mm-stable soon by >> default. So if you want to object to any of it, now's the time ;-). > > I just did :P > > Note that I'm distracted by a tiny human being. I should be back at work tomorrow. Ahh - congratulations! > > Hopefully other people that participated in the discussions can review and ack > in the meantime. That would certainly be nice (hint to everyone else on the thread ;-) > > IMHO there really is no need to rush at this point. I have a couple of selfish reasons; I was hoping to get it into v6.7 since I was thinking that would be the next LTS, but I've just done the maths again, and it looks like it will be v6.6, so I guess I've missed it anyway. The other is that I would like to move focus to other changes that build on this, and that's difficult while this is still not merged. >