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From: Christoph Lameter <clameter@sgi.com>
To: Andrew Morton <akpm@osdl.org>
Cc: nickpiggin@yahoo.com.au, torvalds@osdl.org, ak@muc.de,
	hugh@veritas.com, linux-mm@kvack.org, linux-ia64@vger.kernel.org,
	linux-kernel@vger.kernel.org, benh@kernel.crashing.org
Subject: Re: page table lock patch V15 [0/7]: overview
Date: Wed, 12 Jan 2005 11:06:00 -0800 (PST)	[thread overview]
Message-ID: <Pine.LNX.4.58.0501121055490.11169@schroedinger.engr.sgi.com> (raw)
In-Reply-To: <20050112104326.69b99298.akpm@osdl.org>

On Wed, 12 Jan 2005, Andrew Morton wrote:

> >  So only a very minor improvements for old machines (this one from ~ 98).
>
> OK.  But have you written a test to demonstrate any performance
> regressions?  From, say, the use of atomic ops on ptes?

If I knew of any regressions, I would certain try to deal with them. The
test is written to check for concurrent page fault performance and it has
repeatedly helped me to find problems with page faults. I have used it for
a couple of other patchsets too. If the patch would be available in mm
then it certainly would get more exposure and it may become clear that
there are some regressions.

Introduction of the cmpxchg is one atomic operations that replaces the two
spinlock ops typically necessary in an unpatched kernel. Obtaining the
spinlock requires an spinlock (which is an atomic operation) and then the
release involves a barrier. So there is a net win for all SMP cases as far
as I can see.

  reply	other threads:[~2005-01-12 19:12 UTC|newest]

Thread overview: 286+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <Pine.LNX.4.44.0411061527440.3567-100000@localhost.localdomain>
     [not found] ` <Pine.LNX.4.58.0411181126440.30385@schroedinger.engr.sgi.com>
     [not found]   ` <Pine.LNX.4.58.0411181715280.834@schroedinger.engr.sgi.com>
     [not found]     ` <419D581F.2080302@yahoo.com.au>
     [not found]       ` <Pine.LNX.4.58.0411181835540.1421@schroedinger.engr.sgi.com>
     [not found]         ` <419D5E09.20805@yahoo.com.au>
     [not found]           ` <Pine.LNX.4.58.0411181921001.1674@schroedinger.engr.sgi.com>
     [not found]             ` <1100848068.25520.49.camel@gaston>
2004-11-19 19:42               ` page fault scalability patch V11 [0/7]: overview Christoph Lameter
2004-11-19 19:43                 ` page fault scalability patch V11 [1/7]: sloppy rss Christoph Lameter
2004-11-19 20:50                   ` Hugh Dickins
2004-11-20  1:29                     ` Christoph Lameter
2004-11-22 15:00                       ` Hugh Dickins
2004-11-22 21:50                         ` deferred rss update instead of " Christoph Lameter
2004-11-22 22:11                           ` Andrew Morton
2004-11-22 22:13                             ` Christoph Lameter
2004-11-22 22:17                               ` Benjamin Herrenschmidt
2004-11-22 22:45                               ` Andrew Morton
2004-11-22 22:48                                 ` Christoph Lameter
2004-11-22 23:09                                   ` Nick Piggin
2004-11-22 23:13                                     ` Christoph Lameter
2004-11-22 23:16                                   ` Andrew Morton
2004-11-22 23:19                                     ` Christoph Lameter
2004-11-22 22:22                           ` Linus Torvalds
2004-11-22 22:27                             ` Christoph Lameter
2004-11-22 22:40                               ` Linus Torvalds
2004-12-01 23:41                                 ` page fault scalability patch V12 [0/7]: Overview and performance tests Christoph Lameter
2004-12-01 23:42                                   ` page fault scalability patch V12 [1/7]: Reduce use of thepage_table_lock Christoph Lameter
2004-12-01 23:42                                   ` page fault scalability patch V12 [2/7]: atomic pte operations for ia64 Christoph Lameter
2004-12-01 23:43                                   ` page fault scalability patch V12 [3/7]: universal cmpxchg for i386 Christoph Lameter
2004-12-01 23:43                                   ` page fault scalability patch V12 [4/7]: atomic pte operations " Christoph Lameter
2004-12-01 23:44                                   ` page fault scalability patch V12 [5/7]: atomic pte operations for x86_64 Christoph Lameter
2004-12-01 23:45                                   ` page fault scalability patch V12 [6/7]: atomic pte operations for s390 Christoph Lameter
2004-12-01 23:45                                   ` page fault scalability patch V12 [7/7]: Split counter for rss Christoph Lameter
2005-01-04 19:35                                     ` page fault scalability patch V14 [0/7]: Overview Christoph Lameter
2005-01-04 19:35                                       ` page fault scalability patch V14 [1/7]: Avoid taking page_table_lock Christoph Lameter
2005-01-04 19:36                                       ` page fault scalability patch V14 [2/7]: ia64 atomic pte operations Christoph Lameter
2005-01-04 19:37                                       ` page fault scalability patch V14 [3/7]: i386 universal cmpxchg Christoph Lameter
2005-01-05 11:51                                         ` Roman Zippel
2005-01-04 19:37                                       ` page fault scalability patch V14 [4/7]: i386 atomic pte operations Christoph Lameter
2005-01-04 19:38                                       ` page fault scalability patch V14 [5/7]: x86_64 " Christoph Lameter
2005-01-04 19:46                                         ` Andi Kleen
2005-01-04 19:58                                           ` Christoph Lameter
2005-01-04 20:21                                             ` Andi Kleen
2005-01-04 20:32                                               ` Christoph Lameter
2005-01-11 17:39                                           ` page table lock patch V15 [0/7]: overview Christoph Lameter
2005-01-11 17:40                                             ` page table lock patch V15 [1/7]: Reduce use of page table lock Christoph Lameter
2005-01-11 17:41                                             ` page table lock patch V15 [2/7]: ia64 atomic pte operations Christoph Lameter
2005-01-11 17:41                                             ` page table lock patch V15 [3/7]: i386 universal cmpxchg Christoph Lameter
2005-01-11 17:42                                             ` page table lock patch V15 [4/7]: i386 atomic pte operations Christoph Lameter
2005-01-11 17:43                                             ` page table lock patch V15 [5/7]: x86_64 " Christoph Lameter
2005-01-11 17:43                                             ` page table lock patch V15 [6/7]: s390 " Christoph Lameter
2005-01-11 17:44                                             ` page table lock patch V15 [7/7]: Split RSS counter Christoph Lameter
2005-01-12  5:59                                             ` page table lock patch V15 [0/7]: overview Nick Piggin
2005-01-12  9:42                                               ` Andrew Morton
2005-01-12 12:29                                                 ` Marcelo Tosatti
2005-01-12 12:43                                                 ` Hugh Dickins
2005-01-12 21:22                                                   ` Hugh Dickins
2005-01-12 23:52                                                     ` Christoph Lameter
2005-01-13  2:52                                                       ` Hugh Dickins
2005-01-13 17:05                                                         ` Christoph Lameter
2005-01-12 16:39                                                 ` Christoph Lameter
2005-01-12 16:49                                                   ` Christoph Hellwig
2005-01-12 17:37                                                     ` Christoph Lameter
2005-01-12 17:41                                                       ` Christoph Hellwig
2005-01-12 17:52                                                         ` Christoph Lameter
2005-01-12 18:04                                                           ` Christoph Hellwig
2005-01-12 18:20                                                           ` Andrew Walrond
2005-01-12 18:43                                                   ` Andrew Morton
2005-01-12 19:06                                                     ` Christoph Lameter [this message]
2005-01-14  3:39                                                       ` Roman Zippel
2005-01-14  4:14                                                         ` Andi Kleen
2005-01-14 12:02                                                           ` Roman Zippel
2005-01-12 23:16                                                     ` Nick Piggin
2005-01-12 23:30                                                       ` Andrew Morton
2005-01-12 23:50                                                         ` Nick Piggin
2005-01-12 23:54                                                           ` Christoph Lameter
2005-01-13  0:10                                                             ` Nick Piggin
2005-01-13  0:16                                                               ` Christoph Lameter
2005-01-13  0:42                                                                 ` Nick Piggin
2005-01-13 22:19                                                                   ` Peter Chubb
2005-01-13  3:18                                                                 ` Andi Kleen
2005-01-13 17:11                                                                   ` Christoph Lameter
2005-01-13 17:25                                                                     ` Linus Torvalds
2005-01-13 18:02                                                                     ` Andi Kleen
2005-01-13 18:16                                                                       ` Christoph Lameter
2005-01-13 20:17                                                                         ` Andi Kleen
2005-01-14  1:09                                                                       ` Christoph Lameter
2005-01-14  4:39                                                                         ` Andi Kleen
2005-01-14  4:52                                                                           ` page table lock patch V15 [0/7]: overview II Andi Kleen
2005-01-14  4:59                                                                             ` Nick Piggin
2005-01-14 10:47                                                                               ` Andi Kleen
2005-01-14 10:57                                                                                 ` Nick Piggin
2005-01-14 11:11                                                                                   ` Andi Kleen
2005-01-14 16:57                                                                                     ` Christoph Lameter
2005-01-14  4:54                                                                           ` page table lock patch V15 [0/7]: overview Nick Piggin
2005-01-14 10:46                                                                             ` Andi Kleen
2005-01-14 16:52                                                                           ` Christoph Lameter
2005-01-14 17:01                                                                             ` Andi Kleen
2005-01-14 17:08                                                                               ` Christoph Lameter
2005-01-14 17:11                                                                                 ` Andi Kleen
2005-01-14 17:43                                                                               ` Linus Torvalds
2005-01-28 20:35                                                                               ` page fault scalability patch V16 [0/4]: redesign overview Christoph Lameter
2005-01-28 20:36                                                                                 ` page fault scalability patch V16 [1/4]: avoid intermittent clearing of ptes Christoph Lameter
2005-01-28 20:36                                                                                 ` page fault scalability patch V16 [2/4]: mm counter macros Christoph Lameter
2005-01-28 20:37                                                                                 ` page fault scalability patch V16 [3/4]: Drop page_table_lock in handle_mm_fault Christoph Lameter
2005-02-01  4:08                                                                                   ` Nick Piggin
2005-02-01 18:47                                                                                     ` Christoph Lameter
2005-02-01 19:01                                                                                     ` Christoph Lameter
2005-02-02  0:31                                                                                       ` Nick Piggin
2005-02-02  1:20                                                                                         ` Christoph Lameter
2005-02-02  1:41                                                                                           ` Nick Piggin
2005-02-02  2:49                                                                                             ` Christoph Lameter
2005-02-02  3:09                                                                                               ` Nick Piggin
2005-02-04  6:27                                                                                                 ` Nick Piggin
2005-02-17  0:57                                                                                         ` page fault scalability patchsets update: prezeroing, prefaulting and atomic operations Christoph Lameter
2005-02-24  6:04                                                                                           ` A Proposal for an MMU abstraction layer Christoph Lameter
2005-02-01  4:16                                                                                   ` page fault scalability patch V16 [3/4]: Drop page_table_lock in handle_mm_fault Nick Piggin
2005-02-01  8:20                                                                                     ` Kernel 2.4.21 hangs up baswaraj kasture
2005-02-01  8:35                                                                                       ` Arjan van de Ven
2005-02-01  9:03                                                                                       ` Christian Hildner
2005-02-07  6:14                                                                                         ` Kernel 2.4.21 gives kernel panic at boot time baswaraj kasture
2005-02-01 17:46                                                                                       ` Kernel 2.4.21 hangs up David Mosberger
2005-02-01 17:54                                                                                         ` Markus Trippelsdorf
2005-02-01 18:08                                                                                           ` David Mosberger
2005-02-01 18:44                                                                                     ` page fault scalability patch V16 [3/4]: Drop page_table_lock in handle_mm_fault Christoph Lameter
2005-01-28 20:38                                                                                 ` page fault scalability patch V16 [4/4]: Drop page_table_lock in do_anonymous_page Christoph Lameter
2005-01-13  3:09                                                           ` page table lock patch V15 [0/7]: overview Hugh Dickins
2005-01-13  3:46                                                             ` Nick Piggin
2005-01-13 17:14                                                               ` Christoph Lameter
2005-01-04 21:21                                         ` page fault scalability patch V14 [5/7]: x86_64 atomic pte operations Brian Gerst
2005-01-04 21:26                                           ` Christoph Lameter
2005-01-04 19:38                                       ` page fault scalability patch V14 [6/7]: s390 atomic pte operationsw Christoph Lameter
2005-01-04 19:39                                       ` page fault scalability patch V14 [7/7]: Split RSS counters Christoph Lameter
2004-12-02  0:10                                   ` page fault scalability patch V12 [0/7]: Overview and performance tests Linus Torvalds
2004-12-02  0:55                                     ` Andrew Morton
2004-12-02  1:46                                       ` Christoph Lameter
2004-12-02  6:21                                     ` Jeff Garzik
2004-12-02  6:34                                       ` Andrew Morton
2004-12-02  6:48                                         ` Jeff Garzik
2004-12-02  7:02                                           ` Andrew Morton
2004-12-02  7:26                                             ` Martin J. Bligh
2004-12-02  7:31                                               ` Jeff Garzik
2004-12-02 18:10                                                 ` cliff white
2004-12-02 18:17                                                   ` Gerrit Huizenga
2004-12-02 20:25                                                   ` linux-os
2004-12-08 17:24                                                   ` Anticipatory prefaulting in the page fault handler V1 Christoph Lameter
2004-12-08 17:33                                                     ` Jesse Barnes
2004-12-08 17:56                                                       ` Christoph Lameter
2004-12-08 18:33                                                         ` Jesse Barnes
2004-12-08 21:26                                                         ` David S. Miller
2004-12-08 21:42                                                           ` Linus Torvalds
2004-12-08 17:55                                                     ` Dave Hansen
2004-12-08 19:07                                                     ` Martin J. Bligh
2004-12-08 22:50                                                     ` Martin J. Bligh
2004-12-09 19:32                                                       ` Christoph Lameter
2004-12-10  2:13                                                         ` [OT:HUMOR] " Adam Heath
2004-12-13 14:30                                                         ` Akinobu Mita
2004-12-13 17:10                                                           ` Christoph Lameter
2004-12-13 22:16                                                             ` Martin J. Bligh
2004-12-14  1:32                                                               ` Anticipatory prefaulting in the page fault handler V2 Christoph Lameter
2004-12-14 19:31                                                                 ` Adam Litke
2004-12-15 19:03                                                                   ` Anticipatory prefaulting in the page fault handler V3 Christoph Lameter
2005-01-05  0:29                                                                   ` Anticipatory prefaulting in the page fault handler V4 Christoph Lameter
2004-12-14 12:24                                                             ` Anticipatory prefaulting in the page fault handler V1 Akinobu Mita
2004-12-14 15:25                                                               ` Akinobu Mita
2004-12-14 20:25                                                               ` Christoph Lameter
2004-12-09 10:57                                                     ` Pavel Machek
2004-12-09 11:32                                                       ` Nick Piggin
2004-12-09 17:05                                                       ` Christoph Lameter
2004-12-14 15:28                                                     ` Adam Litke
2004-12-02 18:43                                               ` page fault scalability patch V12 [0/7]: Overview and performance tests cliff white
2004-12-06 19:33                                                 ` Marcelo Tosatti
2004-12-02 16:24                                             ` Gerrit Huizenga
2004-12-02 17:34                                             ` cliff white
2004-12-02 19:48                                           ` Diego Calleja
2004-12-02 20:12                                             ` Jeff Garzik
2004-12-02 20:30                                               ` Diego Calleja
2004-12-02 21:08                                               ` Wichert Akkerman
2004-12-03  0:07                                               ` Francois Romieu
2004-12-02  7:00                                         ` Jeff Garzik
2004-12-02  7:05                                           ` Benjamin Herrenschmidt
2004-12-02  7:11                                             ` Jeff Garzik
2004-12-02 11:16                                               ` Benjamin Herrenschmidt
2004-12-02 14:30                                           ` Andy Warner
2005-01-06 23:40                                             ` Jeff Garzik
2004-12-02 18:27                                         ` Grant Grundler
2004-12-02 18:33                                           ` Andrew Morton
2004-12-02 18:36                                           ` Christoph Hellwig
2004-12-07 10:51                                         ` Pavel Machek
2004-12-09  8:00                                   ` Nick Piggin
2004-12-09 17:03                                     ` Christoph Lameter
2004-12-10  4:30                                       ` Nick Piggin
2004-12-09 18:37                                   ` Hugh Dickins
2004-12-09 22:02                                     ` page fault scalability patch V12: rss tasklist vs sloppy rss Christoph Lameter
2004-12-09 22:52                                       ` Andrew Morton
2004-12-09 22:52                                       ` William Lee Irwin III
2004-12-09 23:07                                         ` Christoph Lameter
2004-12-09 23:29                                           ` William Lee Irwin III
2004-12-09 23:49                                             ` Christoph Lameter
2004-12-10  4:26                                     ` page fault scalability patch V12 [0/7]: Overview and performance tests Nick Piggin
2004-12-10  4:54                                       ` Nick Piggin
2004-12-10  5:06                                         ` Benjamin Herrenschmidt
2004-12-10  5:19                                           ` Nick Piggin
2004-12-10 12:30                                             ` Hugh Dickins
2004-12-10 18:43                                     ` Christoph Lameter
2004-12-10 21:43                                       ` Hugh Dickins
2004-12-10 22:12                                         ` Andrew Morton
2004-12-10 23:52                                           ` Hugh Dickins
2004-12-11  0:18                                             ` Andrew Morton
2004-12-11  0:44                                               ` Hugh Dickins
2004-12-11  0:57                                                 ` Andrew Morton
2004-12-11  9:23                                                   ` Hugh Dickins
2004-12-12  7:54                                       ` Nick Piggin
2004-12-12  9:33                                         ` Hugh Dickins
2004-12-12  9:48                                           ` Nick Piggin
2004-12-12 21:24                                           ` William Lee Irwin III
2004-12-17  3:31                                             ` Christoph Lameter
2004-12-17  3:32                                             ` page fault scalability patch V13 [0/8]: Overview Christoph Lameter
2004-12-17  3:33                                               ` page fault scalability patch V13 [1/8]: Reduce the use of the page_table_lock Christoph Lameter
2004-12-17  3:33                                               ` page fault scalability patch V13 [2/8]: ia64 atomic pte operations Christoph Lameter
2004-12-17  3:34                                               ` page fault scalability patch V13 [3/8]: universal cmpxchg for i386 Christoph Lameter
2004-12-17  3:35                                               ` page fault scalability patch V13 [4/8]: atomic pte operations " Christoph Lameter
2004-12-17  3:36                                               ` page fault scalability patch V13 [5/8]: atomic pte operations for AMD64 Christoph Lameter
2004-12-17  3:38                                               ` page fault scalability patch V13 [7/8]: Split RSS Christoph Lameter
2004-12-17  3:39                                               ` page fault scalability patch V13 [8/8]: Prefaulting using ptep_cmpxchg Christoph Lameter
2004-12-17  5:55                                               ` page fault scalability patch V13 [0/8]: Overview Christoph Lameter
2004-12-10 20:03                                     ` pfault V12 : correction to tasklist rss Christoph Lameter
2004-12-10 21:24                                       ` Hugh Dickins
2004-12-10 21:38                                         ` Andrew Morton
2004-12-11  6:03                                           ` William Lee Irwin III
2004-11-22 22:32                             ` deferred rss update instead of sloppy rss Nick Piggin
2004-11-22 22:39                               ` Christoph Lameter
2004-11-22 23:14                                 ` Nick Piggin
2004-11-19 19:44                 ` page fault scalability patch V11 [2/7]: page fault handler optimizations Christoph Lameter
2004-11-19 19:44                 ` page fault scalability patch V11 [3/7]: ia64 atomic pte operations Christoph Lameter
2004-11-19 19:45                 ` page fault scalability patch V11 [4/7]: universal cmpxchg for i386 Christoph Lameter
2004-11-19 19:46                 ` page fault scalability patch V11 [5/7]: i386 atomic pte operations Christoph Lameter
2004-11-19 19:46                 ` page fault scalability patch V11 [6/7]: x86_64 " Christoph Lameter
2004-11-19 19:47                 ` page fault scalability patch V11 [7/7]: s390 " Christoph Lameter
2004-11-19 19:59                 ` page fault scalability patch V11 [0/7]: overview Linus Torvalds
2004-11-20  1:07                   ` Nick Piggin
2004-11-20  1:29                     ` Christoph Lameter
2004-11-20  1:45                       ` Nick Piggin
2004-11-20  1:58                       ` Linus Torvalds
2004-11-20  2:06                         ` Linus Torvalds
2004-11-20  1:56                     ` Linus Torvalds
2004-11-22 18:06                       ` Bill Davidsen
2004-11-20  2:03                   ` William Lee Irwin III
2004-11-20  2:25                     ` Nick Piggin
2004-11-20  2:41                       ` William Lee Irwin III
2004-11-20  2:46                         ` Nick Piggin
2004-11-20  3:37                     ` Nick Piggin
2004-11-20  3:55                       ` William Lee Irwin III
2004-11-20  4:03                         ` Nick Piggin
2004-11-20  4:06                           ` Nick Piggin
2004-11-20  4:23                           ` William Lee Irwin III
2004-11-20  4:29                             ` Nick Piggin
2004-11-20  5:38                               ` William Lee Irwin III
2004-11-20  5:50                                 ` Nick Piggin
2004-11-20  6:23                                   ` William Lee Irwin III
2004-11-20  6:49                                     ` Nick Piggin
2004-11-20  6:57                                       ` Andrew Morton
2004-11-20  7:04                                         ` Andrew Morton
2004-11-20  7:13                                         ` Nick Piggin
2004-11-20  8:00                                           ` William Lee Irwin III
2004-11-20 16:59                                           ` Martin J. Bligh
2004-11-20 17:14                                             ` Linus Torvalds
2004-11-20 19:08                                               ` William Lee Irwin III
2004-11-20 19:16                                                 ` Linus Torvalds
2004-11-20 19:33                                                   ` William Lee Irwin III
2004-11-22 17:44                                                     ` Christoph Lameter
2004-11-22 22:43                                                       ` William Lee Irwin III
2004-11-22 22:51                                                         ` Christoph Lameter
2004-11-23  2:25                                                           ` William Lee Irwin III
2004-11-20 20:25                                                 ` [OT] " Adam Heath
2004-11-20  7:15                                       ` William Lee Irwin III
2004-11-20  7:29                                         ` Nick Piggin
2004-11-20  7:45                                           ` touch_nmi_watchdog (was: page fault scalability patch V11 [0/7]: overview) Nick Piggin
2004-11-20  7:57                                           ` page fault scalability patch V11 [0/7]: overview Nick Piggin
2004-11-20  8:25                                             ` William Lee Irwin III
2004-11-20  2:04                 ` William Lee Irwin III
2004-11-20  2:18                   ` Nick Piggin
2004-11-20  2:34                     ` William Lee Irwin III
2004-11-20  2:40                       ` Nick Piggin
2004-11-20  3:04                         ` William Lee Irwin III
2004-11-20  3:14                           ` Nick Piggin
2004-11-20  3:43                             ` William Lee Irwin III
2004-11-20  3:58                               ` Nick Piggin
2004-11-20  4:01                                 ` William Lee Irwin III
2004-11-20  4:34                                 ` Robin Holt
2004-11-20  3:33                           ` Robin Holt
2004-11-20  4:24                             ` William Lee Irwin III
2004-11-20  2:06                 ` Robin Holt

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