From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 52832139CE9 for ; Thu, 8 Aug 2024 08:15:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723104908; cv=none; b=G80JoP8XG+GWujV2cpU17JUS/rvCUCMh8fCHP/qqMf22h98DzvN9cp7PFSkY6Otne0H3CbR6pKhJPxlfAVjJDpZH94eSX61i3kHkHTMUUU3tD9LpMiirII7A6q9B8x7sGyS2JhJ+eQuURMk9Npor/8HPD5MThch6hGYK2xH1IR0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723104908; c=relaxed/simple; bh=PjUULOVF16mrDrRsJDcYFYImZ51HZzB6GeEicEhNtik=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=OqG7pb1u78XIlKvqPeQTvHWWwFvHQjN6rgC4CAI8gCx87C4cxlSQ7/iftFaJ6skcX/5o6elLtYFnYY0cOaEcU3B0x1pwMhdSHVLqKkpOLWf4dWQDKWet9SXufhSVcpjD2Rp6XpHb6uO6gQa/pJgELq81Okcvhp8aWr5CpARLDDM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=ftFzSD9t; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ftFzSD9t" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1723104905; 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=oyWJ8Aj+hBX0DWngQENs2Lb+oj2ROH3TU2+agxCUIlc=; b=ftFzSD9tyG6dMnMoxs+h4h38VFZbtgVgRsGfkmhzEDu3CpLK4Ki6vEkXgUs+UfKNNc9ijP SR4VZdFTA/gpnnk3+ll00KHoLC4lF2MPrGRn9S8y+sd9/lzI8JL6C76jLRJNvhGnuSI1lF 7jRlbU4Ok14Tzr4Vuq04+HQAHl+vh+k= Received: from mail-lf1-f70.google.com (mail-lf1-f70.google.com [209.85.167.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-596-8jAJl1fTN5Wgp50H-B3fRQ-1; Thu, 08 Aug 2024 04:15:03 -0400 X-MC-Unique: 8jAJl1fTN5Wgp50H-B3fRQ-1 Received: by mail-lf1-f70.google.com with SMTP id 2adb3069b0e04-530e1f3ed95so695449e87.1 for ; Thu, 08 Aug 2024 01:15:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723104902; x=1723709702; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=oyWJ8Aj+hBX0DWngQENs2Lb+oj2ROH3TU2+agxCUIlc=; b=h0BB3Mlpw4k0u+F3aEO2mA70XdBsXc+8Yl+qsJt/gqunGrDk1UQVBf5q04SP2vHqns e6eIEswCqvsxiV8P11n6NiyLAgMCVR01yDSmUZEHINKDqxrjoruXCmcG+TD3twauCe5Y rKAvv9OlwRr/Uz7aOHZOWpu+YHP9Pjiw8LxU+qyAdKQaduJ6c/bSCddSvBayy6ca1duG r9sLHtiJfacIOG+dLWaDB1PiCwZ5+rihCcgnPUBgS4Xeg8FNO60aCsEmkN5YbXRoa+F3 H1uSAaIMwGwW4942BXtbfAYilqLGmB0iTzRSqxqCUPrQdx/uhHWTGZNRlOciHSP2+ndU DEbA== X-Forwarded-Encrypted: i=1; AJvYcCWERzjhPPNXdAyVlmseB6PJCNuNJFMESxuwNi4y4vcgQ4UHw2/plppUeUSlpKyIa0cs+/79nFo8uxgLCa8=@vger.kernel.org X-Gm-Message-State: AOJu0Yx9CVJp5hXOFqmBy+EIluiPlHn13wzkzWap/9XX8bigtJd/xPGH QdYWpZr4n+EMUZQTzBMIeTgR9jCMbROwgwLCpFINMNgG8uxFK9e0Uk23pQkNSvSKnxxzYmv0LBa wV6GXrwakAE4MjWF4y8fHIwkzb7/iUgwyY01VWBgM0Q+kgV4Km4Tgcm7M1d97yg== X-Received: by 2002:a05:6512:108d:b0:52d:8f80:6444 with SMTP id 2adb3069b0e04-530e58437bemr707690e87.32.1723104902052; Thu, 08 Aug 2024 01:15:02 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHNAYynkuqXr7H0yz8pte8Qo1+3nKFVMeza8PvT3f4ee1PcafCymAQtrrtrAwdkbWDwo9CEhQ== X-Received: by 2002:a05:6512:108d:b0:52d:8f80:6444 with SMTP id 2adb3069b0e04-530e58437bemr707672e87.32.1723104901429; Thu, 08 Aug 2024 01:15:01 -0700 (PDT) Received: from ?IPV6:2003:cb:c713:2a00:f151:50f1:7164:32e6? (p200300cbc7132a00f15150f1716432e6.dip0.t-ipconnect.de. [2003:cb:c713:2a00:f151:50f1:7164:32e6]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-429059bdd72sm60203235e9.39.2024.08.08.01.15.00 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 08 Aug 2024 01:15:00 -0700 (PDT) Message-ID: <95f97482-6270-4ec1-8bd5-9af95614bd5f@redhat.com> Date: Thu, 8 Aug 2024 10:14:59 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 2/2] mm: attempt to batch free swap entries for zap_pte_range() To: Barry Song <21cnbao@gmail.com>, akpm@linux-foundation.org, linux-mm@kvack.org Cc: chrisl@kernel.org, hughd@google.com, justinjiang@vivo.com, kaleshsingh@google.com, kasong@tencent.com, linux-kernel@vger.kernel.org, ryan.roberts@arm.com, v-songbaohua@oppo.com, ying.huang@intel.com References: <20240807215859.57491-1-21cnbao@gmail.com> <20240807215859.57491-3-21cnbao@gmail.com> From: David Hildenbrand Content-Language: en-US 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: <20240807215859.57491-3-21cnbao@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 07.08.24 23:58, Barry Song wrote: > From: Barry Song > > Zhiguo reported that swap release could be a serious bottleneck > during process exits[1]. With mTHP, we have the opportunity to > batch free swaps. > Thanks to the work of Chris and Kairui[2], I was able to achieve > this optimization with minimal code changes by building on their > efforts. > If swap_count is 1, which is likely true as most anon memory are > private, we can free all contiguous swap slots all together. > > Ran the below test program for measuring the bandwidth of munmap > using zRAM and 64KiB mTHP: > > #include > #include > #include > > unsigned long long tv_to_ms(struct timeval tv) > { > return tv.tv_sec * 1000 + tv.tv_usec / 1000; > } > > main() > { > struct timeval tv_b, tv_e; > int i; > #define SIZE 1024*1024*1024 > void *p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, > MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); > if (!p) { > perror("fail to get memory"); > exit(-1); > } > > madvise(p, SIZE, MADV_HUGEPAGE); > memset(p, 0x11, SIZE); /* write to get mem */ > > madvise(p, SIZE, MADV_PAGEOUT); > > gettimeofday(&tv_b, NULL); > munmap(p, SIZE); > gettimeofday(&tv_e, NULL); > > printf("munmap in bandwidth: %ld bytes/ms\n", > SIZE/(tv_to_ms(tv_e) - tv_to_ms(tv_b))); > } > > The result is as below (munmap bandwidth): > mm-unstable mm-unstable-with-patch > round1 21053761 63161283 > round2 21053761 63161283 > round3 21053761 63161283 > round4 20648881 67108864 > round5 20648881 67108864 > > munmap bandwidth becomes 3X faster. > > [1] https://lore.kernel.org/linux-mm/20240731133318.527-1-justinjiang@vivo.com/ > [2] https://lore.kernel.org/linux-mm/20240730-swap-allocator-v5-0-cb9c148b9297@kernel.org/ > > Cc: Kairui Song > Cc: Chris Li > Cc: "Huang, Ying" > Cc: Hugh Dickins > Cc: Kalesh Singh > Cc: Ryan Roberts > Cc: David Hildenbrand > Signed-off-by: Barry Song > --- All looks straight forward to me Acked-by: David Hildenbrand -- Cheers, David / dhildenb