From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zoltan Menyhart Date: Tue, 30 Mar 2004 11:20:34 +0000 Subject: Re: Migrate pages from a ccNUMA node to another - patch Message-Id: <40695802.1F13AB0D@nospam.org> List-Id: References: <4063F581.ACC5C511@nospam.org> <1080321646.31638.105.camel@nighthawk> <20040330082741.541B77054E@sv1.valinux.co.jp> <20040330.180523.08003015.taka@valinux.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: Hirokazu Takahashi Cc: haveblue@us.ibm.com, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, iwamoto@valinux.co.jp Hirokazu Takahashi wrote: >=20 > Hello, >=20 > > > Have you considered any common ground your patch might share with the > > > people doing memory hotplug? > > > > > > http://people.valinux.co.jp/~iwamoto/mh.html > > > > > > They have a similar problem to your migration that occurs when a user > > > wants to remove a whole or partial NUMA node. > > > lhms-devel@lists.sourceforge.net > > > > Processes must be migrated to other nodes when a node is being > > removed. Conversely, processes may be migrated from other nodes when > > a node is added. I'm not familiar with NUMA things, and I think our > > team doesn't have a particular solution. If you have some idea, > > that's great. > > > > BTW, it seems page migration can use my remap_onepage function. Our > > code can move most kinds of pages including hugetlbfs pages and page > > caches. >=20 > I believe his patch will interest you since most of the code is > independent of cpu architecture and it also covers mmaped files, > shmem, ramdisk, mlocked pages and so on. >=20 > We will post new version of the memory hotplug patches in a week. >=20 > Thank you, > Hirokazu Takahashi. I am afraid the "remap_onepage()" function + the modifications necessary at some other places are too much for me :-) You do a couple of retries, waits. I cannot afford spending so much as overhead due to some performance optimization. I can understand that if you want to remove a node / memory module, then you have to succeed by all means, you have to handle all kinds of pages, the performance is not at a premium. Regards, Zolt=E1n Menyh=E1rt