On Wed, May 31, 2017 at 01:59:54PM +1000, Balbir Singh wrote: > On Wed, 24 May 2017 13:20:21 -0400 > Jérôme Glisse <jglisse@xxxxxxxxxx> wrote: > > > This patch add a new memory migration helpers, which migrate memory > > backing a range of virtual address of a process to different memory > > (which can be allocated through special allocator). It differs from > > numa migration by working on a range of virtual address and thus by > > doing migration in chunk that can be large enough to use DMA engine > > or special copy offloading engine. > > > > Expected users are any one with heterogeneous memory where different > > memory have different characteristics (latency, bandwidth, ...). As > > an example IBM platform with CAPI bus can make use of this feature > > to migrate between regular memory and CAPI device memory. New CPU > > architecture with a pool of high performance memory not manage as > > cache but presented as regular memory (while being faster and with > > lower latency than DDR) will also be prime user of this patch. > > > > Migration to private device memory will be useful for device that > > have large pool of such like GPU, NVidia plans to use HMM for that. > > > > It is helpful, for HMM-CDM however we would like to avoid the downsides > of MIGRATE_SYNC_NOCOPY What are the downside you are referring too ? Cheers, Jérôme -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
