From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yasuaki Ishimatsu Subject: Re: [RFC PATCH v3 0/13] memory-hotplug : hot-remove physical memory Date: Wed, 11 Jul 2012 09:09:28 +0900 Message-ID: <4FFCC438.4080004@jp.fujitsu.com> References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFBFCAC.4010007@jp.fujitsu.com> <4FFC5D43.7040206@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:49993 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932069Ab2GKAKE (ORCPT ); Tue, 10 Jul 2012 20:10:04 -0400 In-Reply-To: <4FFC5D43.7040206@gmail.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Jiang Liu Cc: Christoph Lameter , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, rientjes@google.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com, wency@cn.fujitsu.com Hi Jiang, 2012/07/11 1:50, Jiang Liu wrote: > On 07/10/2012 05:58 PM, Yasuaki Ishimatsu wrote: >> Hi Christoph, >> >> 2012/07/10 0:18, Christoph Lameter wrote: >>> >>> On Mon, 9 Jul 2012, Yasuaki Ishimatsu wrote: >>> >>>> Even if you apply these patches, you cannot remove the physical memory >>>> completely since these patches are still under development. I want you to >>>> cooperate to improve the physical memory hot-remove. So please review these >>>> patches and give your comment/idea. >>> >>> Could you at least give a method on how you want to do physical memory >>> removal? >> >> We plan to release a dynamic hardware partitionable system. It will be >> able to hot remove/add a system board which included memory and cpu. >> But as you know, Linux does not support memory hot-remove on x86 box. >> So I try to develop it. >> >> Current plan to hot remove system board is to use container driver. >> Thus I define the system board in ACPI DSDT table as a container device. >> It have supported hot-add a container device. And if container device >> has _EJ0 ACPI method, "eject" file to remove the container device is >> prepared as follow: >> >> # ls -l /sys/bus/acpi/devices/ACPI0004\:01/eject >> --w-------. 1 root root 4096 Jul 10 18:19 /sys/bus/acpi/devices/ACPI0004:01/eject >> >> When I hot-remove the container device, I echo 1 to the file as follow: >> >> #echo 1 > /sys/bus/acpi/devices/ACPI0004\:02/eject >> >> Then acpi_bus_trim() is called. And it calls acpi_memory_device_remove() >> for removing memory device. But the code does not do nothing. >> So I developed the continuation of the function. >> >>> You would have to remove all objects from the range you want to >>> physically remove. That is only possible under special circumstances and >>> with a limited set of objects. Even if you exclusively use ZONE_MOVEABLE >>> you still may get cases where pages are pinned for a long time. >> >> I know it. So my memory hot-remove plan is as follows: >> >> 1. hot-added a system board >> All memory which included the system board is offline. >> >> 2. online the memory as removable page >> The function has not supported yet. It is being developed by Lai as follow: >> http://lkml.indiana.edu/hypermail/linux/kernel/1207.0/01478.html >> If it is supported, I will be able to create movable memory. >> >> 3. hot-remove the memory by container device's eject file > We have implemented a prototype to do physical node (mem + CPU + IOH) hotplug > for Itanium and is now porting it to x86. But with currently solution, memory > hotplug functionality may cause 10-20% performance decrease because we concentrate > all DMA/Normal memory to the first NUMA node, and all other NUMA nodes only > hosts ZONE_MOVABLE. We are working on solution to minimize the performance > drop now. Thank you for your interesting response. I have a question. How do you move all other NUMA nodes to ZONE_MOVABLE? To use ZONE_MOVABLE, we need to use boot options like kernelcore or movablecore. But it is not enough, since the requested amount is spread evenly throughout all nodes in the system. So I think we do not have way to move all other NUMA node to ZONE_MOVABLE. Thanks, Yasuaki Ishimatsu > >> >> Thanks, >> Yasuaki Ishimatsu >> >>> >>> I am not sure that these patches are useful unless we know where you are >>> going with this. If we end up with a situation where we still cannot >>> remove physical memory then this patchset is not helpful. >> >> >> > > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932138Ab2GKAKH (ORCPT ); Tue, 10 Jul 2012 20:10:07 -0400 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:49993 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932069Ab2GKAKE (ORCPT ); Tue, 10 Jul 2012 20:10:04 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.7.4 Message-ID: <4FFCC438.4080004@jp.fujitsu.com> Date: Wed, 11 Jul 2012 09:09:28 +0900 From: Yasuaki Ishimatsu User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Jiang Liu CC: Christoph Lameter , , , , , , , , , , , , Subject: Re: [RFC PATCH v3 0/13] memory-hotplug : hot-remove physical memory References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFBFCAC.4010007@jp.fujitsu.com> <4FFC5D43.7040206@gmail.com> In-Reply-To: <4FFC5D43.7040206@gmail.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jiang, 2012/07/11 1:50, Jiang Liu wrote: > On 07/10/2012 05:58 PM, Yasuaki Ishimatsu wrote: >> Hi Christoph, >> >> 2012/07/10 0:18, Christoph Lameter wrote: >>> >>> On Mon, 9 Jul 2012, Yasuaki Ishimatsu wrote: >>> >>>> Even if you apply these patches, you cannot remove the physical memory >>>> completely since these patches are still under development. I want you to >>>> cooperate to improve the physical memory hot-remove. So please review these >>>> patches and give your comment/idea. >>> >>> Could you at least give a method on how you want to do physical memory >>> removal? >> >> We plan to release a dynamic hardware partitionable system. It will be >> able to hot remove/add a system board which included memory and cpu. >> But as you know, Linux does not support memory hot-remove on x86 box. >> So I try to develop it. >> >> Current plan to hot remove system board is to use container driver. >> Thus I define the system board in ACPI DSDT table as a container device. >> It have supported hot-add a container device. And if container device >> has _EJ0 ACPI method, "eject" file to remove the container device is >> prepared as follow: >> >> # ls -l /sys/bus/acpi/devices/ACPI0004\:01/eject >> --w-------. 1 root root 4096 Jul 10 18:19 /sys/bus/acpi/devices/ACPI0004:01/eject >> >> When I hot-remove the container device, I echo 1 to the file as follow: >> >> #echo 1 > /sys/bus/acpi/devices/ACPI0004\:02/eject >> >> Then acpi_bus_trim() is called. And it calls acpi_memory_device_remove() >> for removing memory device. But the code does not do nothing. >> So I developed the continuation of the function. >> >>> You would have to remove all objects from the range you want to >>> physically remove. That is only possible under special circumstances and >>> with a limited set of objects. Even if you exclusively use ZONE_MOVEABLE >>> you still may get cases where pages are pinned for a long time. >> >> I know it. So my memory hot-remove plan is as follows: >> >> 1. hot-added a system board >> All memory which included the system board is offline. >> >> 2. online the memory as removable page >> The function has not supported yet. It is being developed by Lai as follow: >> http://lkml.indiana.edu/hypermail/linux/kernel/1207.0/01478.html >> If it is supported, I will be able to create movable memory. >> >> 3. hot-remove the memory by container device's eject file > We have implemented a prototype to do physical node (mem + CPU + IOH) hotplug > for Itanium and is now porting it to x86. But with currently solution, memory > hotplug functionality may cause 10-20% performance decrease because we concentrate > all DMA/Normal memory to the first NUMA node, and all other NUMA nodes only > hosts ZONE_MOVABLE. We are working on solution to minimize the performance > drop now. Thank you for your interesting response. I have a question. How do you move all other NUMA nodes to ZONE_MOVABLE? To use ZONE_MOVABLE, we need to use boot options like kernelcore or movablecore. But it is not enough, since the requested amount is spread evenly throughout all nodes in the system. So I think we do not have way to move all other NUMA node to ZONE_MOVABLE. Thanks, Yasuaki Ishimatsu > >> >> Thanks, >> Yasuaki Ishimatsu >> >>> >>> I am not sure that these patches are useful unless we know where you are >>> going with this. If we end up with a situation where we still cannot >>> remove physical memory then this patchset is not helpful. >> >> >> > > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx171.postini.com [74.125.245.171]) by kanga.kvack.org (Postfix) with SMTP id A2C0A6B0073 for ; Tue, 10 Jul 2012 20:10:04 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id AACC93EE081 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 8ED7645DE5A for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 68F6F45DE55 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 5D0D41DB804D for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from g01jpexchyt03.g01.fujitsu.local (g01jpexchyt03.g01.fujitsu.local [10.128.194.42]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 0C1411DB8040 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Message-ID: <4FFCC438.4080004@jp.fujitsu.com> Date: Wed, 11 Jul 2012 09:09:28 +0900 From: Yasuaki Ishimatsu MIME-Version: 1.0 Subject: Re: [RFC PATCH v3 0/13] memory-hotplug : hot-remove physical memory References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFBFCAC.4010007@jp.fujitsu.com> <4FFC5D43.7040206@gmail.com> In-Reply-To: <4FFC5D43.7040206@gmail.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Jiang Liu Cc: Christoph Lameter , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, rientjes@google.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com, wency@cn.fujitsu.com Hi Jiang, 2012/07/11 1:50, Jiang Liu wrote: > On 07/10/2012 05:58 PM, Yasuaki Ishimatsu wrote: >> Hi Christoph, >> >> 2012/07/10 0:18, Christoph Lameter wrote: >>> >>> On Mon, 9 Jul 2012, Yasuaki Ishimatsu wrote: >>> >>>> Even if you apply these patches, you cannot remove the physical memory >>>> completely since these patches are still under development. I want you to >>>> cooperate to improve the physical memory hot-remove. So please review these >>>> patches and give your comment/idea. >>> >>> Could you at least give a method on how you want to do physical memory >>> removal? >> >> We plan to release a dynamic hardware partitionable system. It will be >> able to hot remove/add a system board which included memory and cpu. >> But as you know, Linux does not support memory hot-remove on x86 box. >> So I try to develop it. >> >> Current plan to hot remove system board is to use container driver. >> Thus I define the system board in ACPI DSDT table as a container device. >> It have supported hot-add a container device. And if container device >> has _EJ0 ACPI method, "eject" file to remove the container device is >> prepared as follow: >> >> # ls -l /sys/bus/acpi/devices/ACPI0004\:01/eject >> --w-------. 1 root root 4096 Jul 10 18:19 /sys/bus/acpi/devices/ACPI0004:01/eject >> >> When I hot-remove the container device, I echo 1 to the file as follow: >> >> #echo 1 > /sys/bus/acpi/devices/ACPI0004\:02/eject >> >> Then acpi_bus_trim() is called. And it calls acpi_memory_device_remove() >> for removing memory device. But the code does not do nothing. >> So I developed the continuation of the function. >> >>> You would have to remove all objects from the range you want to >>> physically remove. That is only possible under special circumstances and >>> with a limited set of objects. Even if you exclusively use ZONE_MOVEABLE >>> you still may get cases where pages are pinned for a long time. >> >> I know it. So my memory hot-remove plan is as follows: >> >> 1. hot-added a system board >> All memory which included the system board is offline. >> >> 2. online the memory as removable page >> The function has not supported yet. It is being developed by Lai as follow: >> http://lkml.indiana.edu/hypermail/linux/kernel/1207.0/01478.html >> If it is supported, I will be able to create movable memory. >> >> 3. hot-remove the memory by container device's eject file > We have implemented a prototype to do physical node (mem + CPU + IOH) hotplug > for Itanium and is now porting it to x86. But with currently solution, memory > hotplug functionality may cause 10-20% performance decrease because we concentrate > all DMA/Normal memory to the first NUMA node, and all other NUMA nodes only > hosts ZONE_MOVABLE. We are working on solution to minimize the performance > drop now. Thank you for your interesting response. I have a question. How do you move all other NUMA nodes to ZONE_MOVABLE? To use ZONE_MOVABLE, we need to use boot options like kernelcore or movablecore. But it is not enough, since the requested amount is spread evenly throughout all nodes in the system. So I think we do not have way to move all other NUMA node to ZONE_MOVABLE. Thanks, Yasuaki Ishimatsu > >> >> Thanks, >> Yasuaki Ishimatsu >> >>> >>> I am not sure that these patches are useful unless we know where you are >>> going with this. If we end up with a situation where we still cannot >>> remove physical memory then this patchset is not helpful. >> >> >> > > -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fgwmail6.fujitsu.co.jp (fgwmail6.fujitsu.co.jp [192.51.44.36]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 59E112C0204 for ; Wed, 11 Jul 2012 10:10:06 +1000 (EST) Received: from m3.gw.fujitsu.co.jp (unknown [10.0.50.73]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id CFCB93EE0C1 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id AE9A745DEB9 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 7B00845DEA6 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 6C74D1DB8042 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Received: from g01jpexchyt03.g01.fujitsu.local (g01jpexchyt03.g01.fujitsu.local [10.128.194.42]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 167A41DB8040 for ; Wed, 11 Jul 2012 09:10:02 +0900 (JST) Message-ID: <4FFCC438.4080004@jp.fujitsu.com> Date: Wed, 11 Jul 2012 09:09:28 +0900 From: Yasuaki Ishimatsu MIME-Version: 1.0 To: Jiang Liu Subject: Re: [RFC PATCH v3 0/13] memory-hotplug : hot-remove physical memory References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFBFCAC.4010007@jp.fujitsu.com> <4FFC5D43.7040206@gmail.com> In-Reply-To: <4FFC5D43.7040206@gmail.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Cc: len.brown@intel.com, wency@cn.fujitsu.com, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, paulus@samba.org, minchan.kim@gmail.com, kosaki.motohiro@jp.fujitsu.com, rientjes@google.com, Christoph Lameter , linuxppc-dev@lists.ozlabs.org, akpm@linux-foundation.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Jiang, 2012/07/11 1:50, Jiang Liu wrote: > On 07/10/2012 05:58 PM, Yasuaki Ishimatsu wrote: >> Hi Christoph, >> >> 2012/07/10 0:18, Christoph Lameter wrote: >>> >>> On Mon, 9 Jul 2012, Yasuaki Ishimatsu wrote: >>> >>>> Even if you apply these patches, you cannot remove the physical memory >>>> completely since these patches are still under development. I want you to >>>> cooperate to improve the physical memory hot-remove. So please review these >>>> patches and give your comment/idea. >>> >>> Could you at least give a method on how you want to do physical memory >>> removal? >> >> We plan to release a dynamic hardware partitionable system. It will be >> able to hot remove/add a system board which included memory and cpu. >> But as you know, Linux does not support memory hot-remove on x86 box. >> So I try to develop it. >> >> Current plan to hot remove system board is to use container driver. >> Thus I define the system board in ACPI DSDT table as a container device. >> It have supported hot-add a container device. And if container device >> has _EJ0 ACPI method, "eject" file to remove the container device is >> prepared as follow: >> >> # ls -l /sys/bus/acpi/devices/ACPI0004\:01/eject >> --w-------. 1 root root 4096 Jul 10 18:19 /sys/bus/acpi/devices/ACPI0004:01/eject >> >> When I hot-remove the container device, I echo 1 to the file as follow: >> >> #echo 1 > /sys/bus/acpi/devices/ACPI0004\:02/eject >> >> Then acpi_bus_trim() is called. And it calls acpi_memory_device_remove() >> for removing memory device. But the code does not do nothing. >> So I developed the continuation of the function. >> >>> You would have to remove all objects from the range you want to >>> physically remove. That is only possible under special circumstances and >>> with a limited set of objects. Even if you exclusively use ZONE_MOVEABLE >>> you still may get cases where pages are pinned for a long time. >> >> I know it. So my memory hot-remove plan is as follows: >> >> 1. hot-added a system board >> All memory which included the system board is offline. >> >> 2. online the memory as removable page >> The function has not supported yet. It is being developed by Lai as follow: >> http://lkml.indiana.edu/hypermail/linux/kernel/1207.0/01478.html >> If it is supported, I will be able to create movable memory. >> >> 3. hot-remove the memory by container device's eject file > We have implemented a prototype to do physical node (mem + CPU + IOH) hotplug > for Itanium and is now porting it to x86. But with currently solution, memory > hotplug functionality may cause 10-20% performance decrease because we concentrate > all DMA/Normal memory to the first NUMA node, and all other NUMA nodes only > hosts ZONE_MOVABLE. We are working on solution to minimize the performance > drop now. Thank you for your interesting response. I have a question. How do you move all other NUMA nodes to ZONE_MOVABLE? To use ZONE_MOVABLE, we need to use boot options like kernelcore or movablecore. But it is not enough, since the requested amount is spread evenly throughout all nodes in the system. So I think we do not have way to move all other NUMA node to ZONE_MOVABLE. Thanks, Yasuaki Ishimatsu > >> >> Thanks, >> Yasuaki Ishimatsu >> >>> >>> I am not sure that these patches are useful unless we know where you are >>> going with this. If we end up with a situation where we still cannot >>> remove physical memory then this patchset is not helpful. >> >> >> > >