Hello, With the increasing popularity of memory tiering, the idea of this series is to trigger some discussion around David's[1] system-wide proactive reclaim beyond memcg[2] as well as sysfs as the interface for exporting system-wide tiering information[2]. I am hoping this can be discussed at LSFMM, and while I know many are interested in tiering subjects in general, I have not seen anyone bring this up in the list. There has been some initial discussion towards the need to expose system-wide tiering information to userspace. I thought I'd start with two sysfs files as a node attribute that exports the demotion_node as well as whether or not the node is fast memory. This was considered (and I agree) better than a new /sys/devices/system/tier/tierN/ interface. So, are we going to go this route? If so, what further information is useful for users? Does having instead a /sys/devices/system/node/nodeN/reclaim/ make sense? Applies against Linus' current tree and has only been _gently_ tested. Thanks! Davidlohr Bueso (6): drivers/base/node: cleanup register_node() mm/vmscan: use node_is_toptier helper in node_reclaim mm: make __node_reclaim() more flexible mm: introduce per-node proactive reclaim interface mm/migration: export demotion_path of a node via sysfs mm/migrate: export whether or not tier is toptier in sysfs Documentation/ABI/stable/sysfs-devices-node | 22 ++++ drivers/base/node.c | 68 ++++++++++-- include/linux/migrate.h | 15 +++ include/linux/swap.h | 16 +++ include/trace/events/vmscan.h | 12 +-- mm/migrate.c | 15 +-- mm/vmscan.c | 108 +++++++++++++++----- 7 files changed, 206 insertions(+), 50 deletions(-) -- 2.26.2
