From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753133AbcHPAic (ORCPT ); Mon, 15 Aug 2016 20:38:32 -0400 Received: from ipmail06.adl6.internode.on.net ([150.101.137.145]:13673 "EHLO ipmail06.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752845AbcHPAia (ORCPT ); Mon, 15 Aug 2016 20:38:30 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: A2C/EABTX7JXEAI1LHleg0WBUoJ5g3mdUYxmihuGFwQCAoFPTQIBAQEBAQIGAQEBAQEBAQE3QIRfAQU6HCMQCAMYCSUPBSUDBxoTiDC+SAEBAQcCASQehUSFFYE5AYhhBZlAjw2PTYw3g3iCc4FtKjKFZgSBQQEBAQ Date: Tue, 16 Aug 2016 10:38:26 +1000 From: Dave Chinner To: Linus Torvalds Cc: Mel Gorman , Johannes Weiner , Vlastimil Babka , Bob Peterson , "Kirill A. Shutemov" , "Huang, Ying" , Christoph Hellwig , Wu Fengguang , LKP , Tejun Heo , LKML Subject: Re: [LKP] [lkp] [xfs] 68a9f5e700: aim7.jobs-per-min -13.6% regression Message-ID: <20160816003826.GG16044@dastard> References: <20160815022808.GX19025@dastard> <20160815050016.GY19025@dastard> <20160815222211.GA19025@dastard> <20160815224259.GB19025@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 15, 2016 at 05:15:47PM -0700, Linus Torvalds wrote: > DaveC - does the spinlock contention go away if you just go back to > 4.7? If so, I think it's the new zone thing. But it would be good to > verify - maybe it's something entirely different and it goes back much > further. Same in 4.7 (flat profile numbers climbed higher after this snapshot was taken, as can be seen by the callgraph numbers): 29.47% [kernel] [k] __pv_queued_spin_lock_slowpath 11.59% [kernel] [k] copy_user_generic_string 3.13% [kernel] [k] __raw_callee_save___pv_queued_spin_unlock 2.87% [kernel] [k] __block_commit_write.isra.29 2.02% [kernel] [k] _raw_spin_lock_irqsave 1.77% [kernel] [k] get_page_from_freelist 1.36% [kernel] [k] __wake_up_bit 1.31% [kernel] [k] __radix_tree_lookup 1.22% [kernel] [k] radix_tree_tag_set 1.16% [kernel] [k] clear_page_dirty_for_io 1.14% [kernel] [k] __remove_mapping 1.14% [kernel] [k] _raw_spin_lock 1.00% [kernel] [k] zone_dirty_ok 0.95% [kernel] [k] radix_tree_tag_clear 0.90% [kernel] [k] generic_write_end 0.89% [kernel] [k] __delete_from_page_cache 0.87% [kernel] [k] unlock_page 0.86% [kernel] [k] cancel_dirty_page 0.81% [kernel] [k] up_write 0.80% [kernel] [k] ___might_sleep 0.77% [kernel] [k] _raw_spin_unlock_irqrestore 0.75% [kernel] [k] generic_perform_write 0.72% [kernel] [k] xfs_do_writepage 0.69% [kernel] [k] down_write 0.63% [kernel] [k] shrink_page_list 0.63% [kernel] [k] __xfs_get_blocks 0.61% [kernel] [k] __test_set_page_writeback 0.59% [kernel] [k] free_hot_cold_page 0.57% [kernel] [k] write_cache_pages 0.56% [kernel] [k] __radix_tree_create 0.55% [kernel] [k] __list_add 0.53% [kernel] [k] page_mapping 0.53% [kernel] [k] drop_buffers 0.51% [kernel] [k] xfs_vm_releasepage 0.51% [kernel] [k] free_pcppages_bulk 0.50% [kernel] [k] __list_del_entry 38.07% 38.07% [kernel] [k] __pv_queued_spin_lock_slowpath - 25.52% ret_from_fork - kthread - 24.36% kswapd shrink_zone shrink_zone_memcg.isra.73 shrink_inactive_list - 3.21% worker_thread process_one_work wb_workfn wb_writeback __writeback_inodes_wb writeback_sb_inodes __writeback_single_inode do_writepages xfs_vm_writepages write_cache_pages - 10.06% __libc_pwrite entry_SYSCALL_64_fastpath sys_pwrite64 vfs_write __vfs_write xfs_file_write_iter xfs_file_buffered_aio_write - generic_perform_write - 5.51% xfs_vm_write_begin - 4.94% grab_cache_page_write_begin pagecache_get_page 0.57% __block_write_begin create_page_buffers create_empty_buffers _raw_spin_lock __pv_queued_spin_lock_slowpath - 4.88% xfs_vm_write_end generic_write_end block_write_end __block_commit_write.isra.29 mark_buffer_dirty __set_page_dirty -Dave. -- Dave Chinner david@fromorbit.com