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charset=utf-8 Content-Disposition: inline Received-SPF: pass client-ip=170.10.133.124; envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.25, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juan Quintela , David Edmondson , "Dr . David Alan Gilbert" , "open list:All patches CC here" , =?utf-8?Q?C=C3=A9dric?= Le Goater , Alexey Romko , Zenghui Yu , wanghaibin.wang@huawei.com, Keqian Zhu , Andrey Gruzdev Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Mar 16, 2021 at 08:57:16PM +0800, Kunkun Jiang wrote: > Starting from pss->page, ram_save_host_page() will check every page > and send the dirty pages up to the end of the current host page or > the boundary of used_length of the block. If the host page size is > a huge page, the step "check" will take a lot of time. > > It will improve performance to use migration_bitmap_find_dirty(). > > Tested on Kunpeng 920; VM parameters: 1U 4G (page size 1G) > The time of ram_save_host_page() in the last round of ram saving: > before optimize: 9250us after optimize: 34us > > Signed-off-by: Keqian Zhu > Signed-off-by: Kunkun Jiang Reviewed-by: Peter Xu Thanks, -- Peter Xu