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Tsirkin" , Jason Wang Cc: kernel@openvz.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org References: <20220705083638.29669-1-alexander.atanasov@virtuozzo.com> <7fd5e645-3892-6e0d-de80-08728e29b150@redhat.com> <123b7518-b0c9-171c-9596-73654691ee58@virtuozzo.com> From: Alexander Atanasov In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: ZR0P278CA0186.CHEP278.PROD.OUTLOOK.COM (2603:10a6:910:44::7) To VE1PR08MB4765.eurprd08.prod.outlook.com (2603:10a6:802:a5::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: ec3601dd-cc7b-4dc0-1e35-08da659dc2c3 X-MS-TrafficTypeDiagnostic: DB8PR08MB4985:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: Y/Pd7XIqyvrlPcy21f7LXnBOKVuBqOMj9rvsmRnXrzI2j4JqJKxpaoJxkv5W6Z/j5dWOvG5qvJjrauexDpvSCuxEVk3DRWh3iDTYdxujmougTYh5rdijQvdsDT47K5tDlY4Q97KAduMWSsDxdZtUP8kAtA+Tggk0YVhCS3qTZI6VPL6XzEq0VHuRd6cuJXBXDs0QAlA77bb/mRW4SsK1lQcI0B/nHBaOrjBR5sDjEVjIVfqG9aQT2Py2aNCG5tJ5Akf4zlNVBAx8TuPNOmHd0vWIQf7eSOtEUmyJLc4vX9XuWJBB5SgRTViOwejWDf/asQUHYeKsirFNU50aLEgFmKkcfuJz6xkVt3kwBTyoW7xy9P76OvhYKbQ7IH6LohKU8tDJuZihhlHfDUZdHo8eFanqjVgifvI5nYQMFJ/o3hs/9GXbIjhnH/Jx59+vtvKnnsYQ1xev5CXqVyHLMZXtcOcPHOv/70NWH/zc7JyDS0FHyJBW12Ne5+zkqrzAD1xg2aDJN/1U7b4uSKjGbxx1VvBer4+8yueoeZQclyYV4ThBsW+WrlJD/eRtcOmp1x34mfUPuX14P71ARM9cxu3b9I/exzChlQyRA1Xt7zcl7Pu2QoeuHsY0oNhDKLosEsYzVvDI0UOR4t1sn5Jkxjlt3K6pxgiZXC5GWIwDhbUYXiYhlyAdB/V1PPNGjwpQhTN0Uwbs+HFpgQsspV0vhFtLm2/SRMYaCMwii3EOlJ3HSTmgnVTKIrAxWuZQGDkh2CqBezASkR1/0Io3iaxYj/5OXhteybntW+q+aITmpIJPi4dQFyoSzxTfabu/IrsSp11SAnlQnl4dlQNiMUQFhGLcAicls70LNjhmKMIjPYmQYZipZFjLehxkel+HTR8gYt1F X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:VE1PR08MB4765.eurprd08.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230016)(4636009)(39850400004)(366004)(346002)(396003)(136003)(376002)(52116002)(66946007)(31696002)(4326008)(53546011)(8676002)(44832011)(6512007)(66476007)(41300700001)(478600001)(83380400001)(26005)(2906002)(186003)(6486002)(5660300002)(66556008)(86362001)(31686004)(316002)(36756003)(8936002)(38100700002)(2616005)(38350700002)(110136005)(6506007)(45980500001)(43740500002);DIR:OUT;SFP:1102; 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>>>> + >>>> + /* Total Memory for the guest from host */ >>>> + seq_printf(f, "%-22s: %lu\n", "total_pages", >>>> + guest_to_balloon_pages(i.totalram)); >>> totalram is calculated from totalram_pages(). >>> >>> When we inflate/deflate, we adjust totalram as well via >>> adjust_managed_page_count(). >> That is true only when not using DEFLATE_ON_OOM. >> >> Otherwise inflated memory is accounted as used and total ram stays the same. >>> Consequently, this doesn't calculate what you actually want? >>> Total memory would be totalram+inflated, current would be totalram. >> My calculations are correct for the case deflate_on_oom is enabled. >> > Which is the corner cases. You'd have to special case on DEFLATE_ON_OOM > availability. Besides checking the features? > >>> But, TBH, only export num_pages. User space can just lookup the other >>> information (totalram) via /proc/meminfo. >> I have missed that the memory accounting is made differently depending >> on a flag. >> >> Since the calculations are different i'd prefer to have the values >> calculate and printed there. > What about an indication instead, whether or not inflated pages are > accounted into total or not? That would be slightly cleaner IMHO. If you care if they are included or not you can check the features and see if the flag is enabled or not. Going vice versa is not so easy to calculate the final values. Please, see the v5. -- Regards, Alexander Atanasov