From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx153.postini.com [74.125.245.153]) by kanga.kvack.org (Postfix) with SMTP id 680EC6B0088 for ; Tue, 20 Nov 2012 07:32:02 -0500 (EST) Received: by mail-bk0-f41.google.com with SMTP id jg9so2806986bkc.14 for ; Tue, 20 Nov 2012 04:32:00 -0800 (PST) Date: Tue, 20 Nov 2012 13:31:56 +0100 From: Ingo Molnar Subject: Re: [PATCH] x86/mm: Don't flush the TLB on #WP pmd fixups Message-ID: <20121120123156.GA15798@gmail.com> References: <1353291284-2998-1-git-send-email-mingo@kernel.org> <20121119162909.GL8218@suse.de> <20121120060014.GA14065@gmail.com> <20121120074445.GA14539@gmail.com> <20121120090637.GA14873@gmail.com> <20121120120251.GA15742@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121120120251.GA15742@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Peter Zijlstra , Paul Turner , Lee Schermerhorn , Christoph Lameter , Rik van Riel , Andrew Morton , Andrea Arcangeli , Linus Torvalds , Thomas Gleixner , Johannes Weiner , Hugh Dickins * Ingo Molnar wrote: > * Ingo Molnar wrote: > > > numa/core profile: > > > > 95.66% perf-1201.map [.] 0x00007fe4ad1c8fc7 > > 1.70% libjvm.so [.] 0x0000000000381581 > > 0.59% [vdso] [.] 0x0000000000000607 > > 0.19% [kernel] [k] do_raw_spin_lock > > 0.11% [kernel] [k] generic_smp_call_function_interrupt > > 0.11% [kernel] [k] timekeeping_get_ns.constprop.7 > > 0.08% [kernel] [k] ktime_get > > 0.06% [kernel] [k] get_cycles > > 0.05% [kernel] [k] __native_flush_tlb > > 0.05% [kernel] [k] rep_nop > > 0.04% perf [.] add_hist_entry.isra.9 > > 0.04% [kernel] [k] rcu_check_callbacks > > 0.04% [kernel] [k] ktime_get_update_offsets > > 0.04% libc-2.15.so [.] __strcmp_sse2 > > > > No page fault overhead (see the page fault rate further below) > > - the NUMA scanning overhead shows up only through some mild > > TLB flush activity (which I'll fix btw). > > The patch attached below should get rid of that mild TLB > flushing activity as well. This has further increased SPECjbb from 203k/sec to 207k/sec, i.e. it's now 5% faster than mainline - THP enabled. The profile is now totally flat even during a full 32-WH SPECjbb run, with the highest overhead entries left all related to timer IRQ processing or profiling. That is on a system that should be very close to yours. Thanks, Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org