Hi Baolin, On Tue, 21 Dec 2021 17:18:02 +0800 Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> wrote: > Hi, > > Now on tiered memory system with different memory types, the reclaim path in > shrink_page_list() already support demoting pages to slow memory node instead > of discarding the pages. However, at that time the fast memory node memory > wartermark is already tense, which will increase the memory allocation latency > during page demotion. So a new method from user space demoting cold pages > proactively will be more helpful. > > We can rely on the DAMON in user space to help to monitor the cold memory on > fast memory node, and demote the cold pages to slow memory node proactively to > keep the fast memory node in a healthy state. > > This patch set introduces a new scheme named DAMOS_DEMOTE to support this feature, > and works well from my testing. Any comments are welcome. Thanks. I like the idea, thank you for these patches! If possible, could you share some details about your tests? Thanks, SJ > > > Baolin Wang (2): > mm: Export the alloc_demote_page() function > mm/damon: Add a new scheme to support demotion on tiered memory system > > include/linux/damon.h | 3 + > mm/damon/dbgfs.c | 1 + > mm/damon/vaddr.c | 156 ++++++++++++++++++++++++++++++++++++++++++++++++++ > mm/internal.h | 1 + > mm/vmscan.c | 2 +- > 5 files changed, 162 insertions(+), 1 deletion(-) > > -- > 1.8.3.1
