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[209.85.220.65]) by mx.google.com with SMTPS id q11sor19622156qtq.28.2019.04.02.12.49.05 for (Google Transport Security); Tue, 02 Apr 2019 12:49:05 -0700 (PDT) Received-SPF: pass (google.com: domain of mst@redhat.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; spf=pass (google.com: domain of mst@redhat.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=mst@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com X-Google-Smtp-Source: APXvYqyssdHTS/DKlsZsXRC9d0R0s3gdduOA5QVLCvuRf6QzAqxPUhlhL0TEas0IduN6EdWwMJPg8g== X-Received: by 2002:ac8:21c7:: with SMTP id 7mr58333120qtz.66.1554234544899; Tue, 02 Apr 2019 12:49:04 -0700 (PDT) Received: from redhat.com ([66.187.232.66]) by smtp.gmail.com with ESMTPSA id a75sm6940361qkg.84.2019.04.02.12.49.02 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 02 Apr 2019 12:49:03 -0700 (PDT) Date: Tue, 2 Apr 2019 15:49:00 -0400 From: "Michael S. Tsirkin" To: David Hildenbrand Cc: Alexander Duyck , Nitesh Narayan Lal , kvm list , LKML , linux-mm , Paolo Bonzini , lcapitulino@redhat.com, pagupta@redhat.com, Yang Zhang , Rik van Riel , dodgen@google.com, Konrad Rzeszutek Wilk , dhildenb@redhat.com, Andrea Arcangeli , Dave Hansen Subject: Re: On guest free page hinting and OOM Message-ID: <20190402154732-mutt-send-email-mst@kernel.org> References: <20190401104608-mutt-send-email-mst@kernel.org> <6a612adf-e9c3-6aff-3285-2e2d02c8b80d@redhat.com> <20190402112115-mutt-send-email-mst@kernel.org> <3dd76ce6-c138-b019-3a43-0bb0b793690a@redhat.com> <6b0a3610-0e7b-08dc-8b5f-707062f87bea@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Tue, Apr 02, 2019 at 08:21:30PM +0200, David Hildenbrand wrote: > The other extreme is a system that barely frees (MAX_ORDER - X) pages, > however your thread will waste cycles scanning for such. I don't think we need to scan as such. An arch hook that queues a job to a wq only when there's work to do will fix the issue, right? -- MST