On Mon, Oct 12, 2020 at 7:57 PM Zengtao (B) <prime.z...@hisilicon.com> wrote: > > > > -----Original Message----- > > From: yulei.ker...@gmail.com [mailto:yulei.ker...@gmail.com] > > Sent: Thursday, October 08, 2020 3:54 PM > > To: a...@linux-foundation.org; naoya.horigu...@nec.com; > > v...@zeniv.linux.org.uk; pbonz...@redhat.com > > Cc: linux-fsde...@vger.kernel.org; k...@vger.kernel.org; > > linux-kernel@vger.kernel.org; xiaoguangrong.e...@gmail.com; > > kernel...@gmail.com; lihaiwei.ker...@gmail.com; Yulei Zhang > > Subject: [PATCH 00/35] Enhance memory utilization with DMEMFS > > > > From: Yulei Zhang <yuleixzh...@tencent.com> > > > > In current system each physical memory page is assocaited with > > a page structure which is used to track the usage of this page. > > But due to the memory usage rapidly growing in cloud environment, > > we find the resource consuming for page structure storage becomes > > highly remarkable. So is it an expense that we could spare? > > > > This patchset introduces an idea about how to save the extra > > memory through a new virtual filesystem -- dmemfs. > > > > Dmemfs (Direct Memory filesystem) is device memory or reserved > > memory based filesystem. This kind of memory is special as it > > is not managed by kernel and most important it is without 'struct page'. > > Therefore we can leverage the extra memory from the host system > > to support more tenants in our cloud service. > > > > We uses a kernel boot parameter 'dmem=' to reserve the system > > memory when the host system boots up, the details can be checked > > in /Documentation/admin-guide/kernel-parameters.txt. > > > > Theoretically for each 4k physical page it can save 64 bytes if > > we drop the 'struct page', so for guest memory with 320G it can > > save about 5G physical memory totally. > > Sounds interesting, but seems your patch only support x86, have you > considered aarch64? > > Regards > Zengtao
Thanks, so far we only verify it on x86 server, may extend to arm platform in the future.
