From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6566CC4332F for ; Wed, 19 Oct 2022 02:06:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229862AbiJSCGf (ORCPT ); Tue, 18 Oct 2022 22:06:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229584AbiJSCGd (ORCPT ); Tue, 18 Oct 2022 22:06:33 -0400 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B24752E9EB for ; Tue, 18 Oct 2022 19:06:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1666145192; x=1697681192; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=wJzOhrQWqcsuSASOVqRvm9mp5Iy2u4n3d/wxjNCySmY=; b=D7pjHk+Jnjh3GKowbN6J8mFGOq9d49cKkjoeIIt2IvfUM4W/QpN83L/6 wsvBhfdt4jVFFTGN3flWnY7wo37/ZzCyb97rWLX2JL4EqWBtVNaPTJcoU 7AxPaYzdx/+qkFxhQUUBZStGIBW38tT3kqIxrlonuA84IkOZbPDGbLiwi 1U6GF3aK82J2UjuETHx+mkqpmsTPuSaWRvCZ+o1r4J6d59P2dPFUiHXFn 23Ao92bd4sa+QMj7FHK5T82D368a1UjZnqbqStxKi2IVgfgqeLlwaHCYk zVqFZionukwP0V6KpuEt/AkJWNkFvwZWcozTJyxzqgLGfWWbXPw7KflQ5 g==; X-IronPort-AV: E=McAfee;i="6500,9779,10504"; a="286001158" X-IronPort-AV: E=Sophos;i="5.95,194,1661842800"; d="scan'208";a="286001158" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Oct 2022 19:06:32 -0700 X-IronPort-AV: E=McAfee;i="6500,9779,10504"; a="874201142" X-IronPort-AV: E=Sophos;i="5.95,194,1661842800"; d="scan'208";a="874201142" Received: from yhuang6-desk2.sh.intel.com (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.238.208.55]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Oct 2022 19:06:29 -0700 From: "Huang, Ying" To: kernel test robot Cc: Rik van Riel , , , Andrew Morton , Yang Shi , Matthew Wilcox , , , , , Subject: Re: [mm] f35b5d7d67: will-it-scale.per_process_ops -95.5% regression References: <202210181535.7144dd15-yujie.liu@intel.com> Date: Wed, 19 Oct 2022 10:05:50 +0800 In-Reply-To: <202210181535.7144dd15-yujie.liu@intel.com> (kernel test robot's message of "Tue, 18 Oct 2022 16:44:59 +0800") Message-ID: <87edv4r2ip.fsf@yhuang6-desk2.ccr.corp.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Yujie, > 32528 48% +147.6% 80547 38% numa-meminfo.node0.AnonHugePages > 92821 23% +59.3% 147839 28% numa-meminfo.node0.AnonPages The Anon pages allocated are much more than the parent commit. This is expected, because THP instead of normal page will be allocated for aligned memory area. > 95.23 -79.8 15.41 6% perf-profile.calltrace.cycles-pp.__munmap > 95.08 -79.7 15.40 6% perf-profile.calltrace.cycles-pp.entry_SYSCALL_64_after_hwframe.__munmap > 95.02 -79.6 15.39 6% perf-profile.calltrace.cycles-pp.do_syscall_64.entry_SYSCALL_64_after_hwframe.__munmap > 94.96 -79.6 15.37 6% perf-profile.calltrace.cycles-pp.__x64_sys_munmap.do_syscall_64.entry_SYSCALL_64_after_hwframe.__munmap > 94.95 -79.6 15.37 6% perf-profile.calltrace.cycles-pp.__vm_munmap.__x64_sys_munmap.do_syscall_64.entry_SYSCALL_64_after_hwframe.__munmap > 94.86 -79.5 15.35 6% perf-profile.calltrace.cycles-pp.__do_munmap.__vm_munmap.__x64_sys_munmap.do_syscall_64.entry_SYSCALL_64_after_hwframe > 94.38 -79.2 15.22 6% perf-profile.calltrace.cycles-pp.unmap_region.__do_munmap.__vm_munmap.__x64_sys_munmap.do_syscall_64 > 42.74 -42.7 0.00 perf-profile.calltrace.cycles-pp.lru_add_drain.unmap_region.__do_munmap.__vm_munmap.__x64_sys_munmap > 42.74 -42.7 0.00 perf-profile.calltrace.cycles-pp.lru_add_drain_cpu.lru_add_drain.unmap_region.__do_munmap.__vm_munmap > 42.72 -42.7 0.00 perf-profile.calltrace.cycles-pp.folio_batch_move_lru.lru_add_drain_cpu.lru_add_drain.unmap_region.__do_munmap > 41.84 -41.8 0.00 perf-profile.calltrace.cycles-pp.folio_lruvec_lock_irqsave.folio_batch_move_lru.lru_add_drain_cpu.lru_add_drain.unmap_region > 41.70 -41.7 0.00 perf-profile.calltrace.cycles-pp._raw_spin_lock_irqsave.folio_lruvec_lock_irqsave.folio_batch_move_lru.lru_add_drain_cpu.lru_add_drain > 41.62 -41.6 0.00 perf-profile.calltrace.cycles-pp.folio_lruvec_lock_irqsave.release_pages.tlb_batch_pages_flush.tlb_finish_mmu.unmap_region > 41.55 -41.6 0.00 perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock_irqsave.folio_lruvec_lock_irqsave.folio_batch_move_lru.lru_add_drain_cpu > 41.52 -41.5 0.00 perf-profile.calltrace.cycles-pp._raw_spin_lock_irqsave.folio_lruvec_lock_irqsave.release_pages.tlb_batch_pages_flush.tlb_finish_mmu > 41.28 -41.3 0.00 perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock_irqsave.folio_lruvec_lock_irqsave.release_pages.tlb_batch_pages_flush In the parent commit, most CPU cycles are used for contention on LRU lock. > 0.00 +4.8 4.82 7% perf-profile.calltrace.cycles-pp.do_huge_pmd_anonymous_page.__handle_mm_fault.handle_mm_fault.do_user_addr_fault.exc_page_fault > 0.00 +4.9 4.88 7% perf-profile.calltrace.cycles-pp.zap_huge_pmd.zap_pmd_range.unmap_page_range.unmap_vmas.unmap_region > 0.00 +8.2 8.22 8% perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock.rmqueue_bulk.rmqueue.get_page_from_freelist > 0.00 +8.2 8.23 8% perf-profile.calltrace.cycles-pp._raw_spin_lock.rmqueue_bulk.rmqueue.get_page_from_freelist.__alloc_pages > 0.00 +8.3 8.35 8% perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock.free_pcppages_bulk.free_unref_page.release_pages > 0.00 +8.3 8.35 8% perf-profile.calltrace.cycles-pp._raw_spin_lock.free_pcppages_bulk.free_unref_page.release_pages.tlb_batch_pages_flush > 0.00 +8.4 8.37 8% perf-profile.calltrace.cycles-pp.free_pcppages_bulk.free_unref_page.release_pages.tlb_batch_pages_flush.tlb_finish_mmu > 0.00 +9.6 9.60 6% perf-profile.calltrace.cycles-pp.free_unref_page.release_pages.tlb_batch_pages_flush.tlb_finish_mmu.unmap_region > 0.00 +65.5 65.48 2% perf-profile.calltrace.cycles-pp.clear_page_erms.clear_huge_page.__do_huge_pmd_anonymous_page.__handle_mm_fault.handle_mm_fault > 0.00 +72.5 72.51 2% perf-profile.calltrace.cycles-pp.clear_huge_page.__do_huge_pmd_anonymous_page.__handle_mm_fault.handle_mm_fault.do_user_addr_fault With the commit, most CPU cycles are consumed for clear huge page. This is expected. We allocate more pages, so, we need more cycles to clear them. Check the source code of test case (will-it-scale/malloc1), I found that it will allocate some memory with malloc() then free it. In the parent commit, because the virtual memory address isn't aligned with 2M, normal page will be allocated. With the commit, THP will be allocated, so more page clearing and less LRU lock contention. I think this is the expected behavior of the commit. And the test case isn't so popular (malloc() then free() but don't access the memory allocated). So this regression isn't important. We can just ignore it. Best Regards, Huang, Ying