On Thu, Nov 2, 2023 at 1:42 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > On Wed, Nov 01, 2023 at 04:08:16PM -0700, Sourav Panda wrote: > > Adds a new per-node PageMetadata field to > > /sys/devices/system/node/nodeN/meminfo > > No, this file is already an abuse of sysfs and we need to get rid of it > (it has multiple values in one file.) Please do not add to the > nightmare by adding new values. Hi Greg, Today, nodeN/meminfo is a counterpart of /proc/meminfo, they contain almost identical fields, but show node-wide and system-wide views. Since per-page metadata is added into /proc/meminfo, it is logical to add into nodeN/meminfo, some nodes can have more or less struct page data based on size of the node, and also the way memory is configured, such as use of vmemamp optimization etc, therefore this information is useful to users. I am not aware of any example of where a system-wide field from /proc/meminfo is represented as a separate sysfs file under node0/. If nodeN/meminfo is ever broken down into separate files it will affect all the fields in it the same way with or without per-page metadata > Also, even if you did want to do this, you didn't document it properly > in Documentation/ABI/ :( The documentation for the fields in nodeN/meminfo is only specified in Documentation/filesystems/proc.rst, there is no separate sysfs Documentation for the fields in this file, we could certainly add that. Thank you, Pasha
