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 A4C9FC54E67 for ; Wed, 27 Mar 2024 11:35:51 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EC9246B0089; Wed, 27 Mar 2024 07:35:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E79496B008A; Wed, 27 Mar 2024 07:35:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D19A96B0092; Wed, 27 Mar 2024 07:35:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id B4A9D6B0089 for ; Wed, 27 Mar 2024 07:35:50 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 406F480CDA for ; Wed, 27 Mar 2024 11:35:50 +0000 (UTC) X-FDA: 81942614460.11.97A8AE3 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf19.hostedemail.com (Postfix) with ESMTP id E62E11A000F for ; Wed, 27 Mar 2024 11:35:47 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=EQ+BDz5e; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf19.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1711539348; 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:dkim-signature; bh=l1N9isGvc9fmkuZfSgg4w1ze51YYDu+2ukxat4LD1r0=; b=YSlSttccBiREqnlcBzpHXHduB/+M2lUCpfo7kkDISo2yOukqm/aT/7lgFzTNdZg354ySWn mk/0A3GvaNtFJrG+F3efjIAZnVea4CuSRlItqYrRxzFUGNNFTRE4fPD0sTl7k5Kd+SqNUJ TmmEsDoP+p8buytL23Yy5MBPvv0aRLM= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=EQ+BDz5e; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf19.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1711539348; a=rsa-sha256; cv=none; b=WLgXqnoWgQVL/sm4WpIKfMluE7zkelpjqXz2UocfL7Jzf8S76ilASiS6/R4zSqUGHLTJ9n AQEpGGeb0jJoMVYfwKTNmNjQKiuqLqoad/3zZpITxI2xp8i9ccCwOdaxYV0y4DE82RPYno 0lV1FkUJgBPnrDfyicB6S3KbKCm6jy0= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1711539347; h=from:from: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:autocrypt:autocrypt; bh=l1N9isGvc9fmkuZfSgg4w1ze51YYDu+2ukxat4LD1r0=; b=EQ+BDz5e9lrWuUxU43IThHadtPW+sBgNk0gufsKve2uBYyh9tMiRo35RGGmNZ1RMypj9yb MRn9Ya1gW6u6yQ5W6XXPeW+S6daaP4L1QsFH9shPd1D0YvKRgcX2Upu7pm8jzPEYx71kSf xCquUkUTYSeBBxmnJ+ccz+//ISdnB+s= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-116-mP_XCrThO3OP5QNJLm943A-1; Wed, 27 Mar 2024 07:35:43 -0400 X-MC-Unique: mP_XCrThO3OP5QNJLm943A-1 Received: by mail-wm1-f70.google.com with SMTP id 5b1f17b1804b1-412c7ee0c97so32256565e9.0 for ; Wed, 27 Mar 2024 04:35:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711539342; x=1712144142; h=content-transfer-encoding:in-reply-to:organization:autocrypt:from :references:cc:to:content-language:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=l1N9isGvc9fmkuZfSgg4w1ze51YYDu+2ukxat4LD1r0=; b=wPkWMSiY4LagOkQoapZTBKlOOZvzIW8iqqfz3Txo6uhoCpDwhKT0LJpHx4b0DQ56eM DBgpLVZixIrhfIZfjM0iFCZeh/rLYM0DrKTk7cWdenXJSShPeWR67reBmDnhbiP8502a Ux1P3rPM4yo+ZtCxxBOmx+UIiA9aagL3vS6t1oa1awruOTumit1/Bq/mWC+SsvdQXVUO HPor7KxG3EP3ucxrnCYLDShPJ9LMsLm+WSA5Ez63/6Mhc+NwEXPJK1vAaAtbDfXo+TYa EMxC9B1ij9+HqqP/cubKRArLUoAsjiSEa8QziZZdFx4wbybh33QFRepStXAjKuKtpicn c7oA== X-Forwarded-Encrypted: i=1; AJvYcCWBrNvkfd5Dp6llgVnkoeb6kofC4J5PvsIPlOpWLQUzzVbKa71+5FygMVqYBrO31Q73UtzSMKvJo5TwNgk+HksQFzs= X-Gm-Message-State: AOJu0Yx5m8Oj1t8D2j42daQg5gkd+ZQx0CvIVK3JVcLHq80BGiSFxdei L3KiRWrE+/RuiHrnx9a4ELz+cRdbTH8WA9hgy6Jv6fNyryGfKLi72SoRPKCN0soGsPqY/B6ZljF yZGda6tKCjzgMCWPlt711yXowDzIkKx8AHXJau7bw3TPvAlJq X-Received: by 2002:a7b:c043:0:b0:414:bfd:379d with SMTP id u3-20020a7bc043000000b004140bfd379dmr844291wmc.22.1711539341878; Wed, 27 Mar 2024 04:35:41 -0700 (PDT) X-Google-Smtp-Source: AGHT+IG6waG+MmhizHt66OpmeHl++C7QDMyBddXLAjdGcwhbvUOUkWfBkC8brHzxLidXPpwHaz4nhQ== X-Received: by 2002:a7b:c043:0:b0:414:bfd:379d with SMTP id u3-20020a7bc043000000b004140bfd379dmr844276wmc.22.1711539341432; Wed, 27 Mar 2024 04:35:41 -0700 (PDT) Received: from ?IPV6:2003:cb:c708:8a00:362b:7e34:a3bc:9ddf? (p200300cbc7088a00362b7e34a3bc9ddf.dip0.t-ipconnect.de. [2003:cb:c708:8a00:362b:7e34:a3bc:9ddf]) by smtp.gmail.com with ESMTPSA id k33-20020a05600c1ca100b0041409cabb39sm1871732wms.18.2024.03.27.04.35.40 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 27 Mar 2024 04:35:41 -0700 (PDT) Message-ID: <330c90c6-87ef-4497-a9c7-739dcd686ca2@redhat.com> Date: Wed, 27 Mar 2024 12:35:39 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH] mm: show mthp_fault_alloc and mthp_fault_fallback of multi-size THPs To: Barry Song <21cnbao@gmail.com>, Matthew Wilcox , ryan.roberts@arm.com, yuzhao@google.com Cc: akpm@linux-foundation.org, linux-mm@kvack.org, kasong@tencent.com, yosryahmed@google.com, cerasuolodomenico@gmail.com, surenb@google.com, Barry Song , Johannes Weiner References: <20240326030103.50678-1-21cnbao@gmail.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: E62E11A000F X-Stat-Signature: 7xedynp9r393ypg7resz7ar79r17y6wb X-Rspam-User: X-HE-Tag: 1711539347-931553 X-HE-Meta: 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 DRv9gXnp 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 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: List-Subscribe: List-Unsubscribe: On 26.03.24 23:19, Barry Song wrote: > On Tue, Mar 26, 2024 at 4:40 PM Barry Song <21cnbao@gmail.com> wrote: >> >> On Tue, Mar 26, 2024 at 4:25 PM Matthew Wilcox wrote: >>> >>> On Tue, Mar 26, 2024 at 04:01:03PM +1300, Barry Song wrote: >>>> Profiling a system blindly with mTHP has become challenging due >>>> to the lack of visibility into its operations. While displaying >>>> additional statistics such as partial map/unmap actions may >>>> spark debate, presenting the success rate of mTHP allocations >>>> appears to be a straightforward and pressing need. >>> >>> Ummm ... no? Not like this anyway. It has the bad assumption that >>> "mTHP" only comes in one size. >> >> >> I had initially considered per-size allocation and fallback before sending >> the RFC. However, in order to prompt discussion and exploration >> into profiling possibilities, I opted to send the simplest code instead. >> >> We could consider two options for displaying per-size statistics. >> >> 1. A single file could be used to display data for all sizes. >> 1024KiB fault allocation: >> 1024KiB fault fallback: >> 512KiB fault allocation: >> 512KiB fault fallback: >> .... >> 64KiB fault allocation: >> 64KiB fault fallback: >> >> 2. A separate file for each size >> For example, >> >> /sys/kernel/debug/transparent_hugepage/hugepages-1024kB/vmstat >> /sys/kernel/debug/transparent_hugepage/hugepages-512kB/vmstat >> ... >> /sys/kernel/debug/transparent_hugepage/hugepages-64kB/vmstat >> > > Hi Ryan, David, Willy, Yu, Hi! > > I'm collecting feedback on whether you'd prefer access to something similar > to /sys/kernel/debug/transparent_hugepage/hugepages-/stat to help > determine the direction to take for this patch. I discussed in the past that we might want to place statistics into sysfs. The idea was to place them into our new hierarchy: /sys/kernel/mm/transparent_hugepage/hugepages-1024kB/... following the "one value per file" sysfs design principle. We could have a new folder "stats" in there that contains files with statistics we care about. Of course, we could also place that initially into debugfs in a similar fashion, and move it over once the interface is considered good and stable. My 2 cents would be to avoid a "single file". > > This is important to us because we're keen on understanding how often > folios allocations fail on a system with limited memory, such as a phone. > > Presently, I've observed a success rate of under 8% for 64KiB allocations. > Yet, integrating Yu's TAO optimization [1] and establishing an 800MiB > nomerge zone on a phone with 8GiB memory, there's a substantial > enhancement in the success rate, reaching approximately 40%. I'm still > fine-tuning the optimal size for the zone. Just as a side note: I didn't have the capacity to comment in detail on the "new zones" proposal in-depth so far (I'm hoping / assume there will be discussions at LSF/MM), but I'm hoping we can avoid that for now and instead improve our pageblock infrastructure, like Johannes is trying to, to achieve similar gains. I suspect "some things we can do with new zones we can also do with pageblocks inside a zone". For example, there were discussions in the past to have "sticky movable" pageblocks: pageblocks that may only contain movable data. One could do the same with "pageblocks may not contain allocations < order X" etc. So one could similarly optimize the memmap to some degree for these pageblocks. IMHO we should first try making THP <= pageblock allocations more reliable, not using new zones, and I'm happy that Johannes et al. are doing work in that direction. But it's a longer discussion to be had at LSF/MM. -- Cheers, David / dhildenb