Hello, On Mon, Jan 25, 2021 at 05:04:00PM -0800, Dave Hansen wrote: > Which part? Large production environments don't trust data from > debugfs? Or don't trust it if it might have been reset?
When the last reset was. Not saying it's impossible or anything but in general it's a lot better to have the counters to be monotonically increasing with time/event stamped markers than the counters themselves getting reset or modified in other ways because the ownership of a specific counter might not be obvious to everyone and accidents and mistakes happen. Note that the "time/event stamped markers" above don't need to and shouldn't be in the kernel. It can be managed by whoever that wants to monitor a given time period and there can be any number of them. > You could stick the "reset" switch in debugfs, and dump something out in > dmesg like we do for /proc/sys/vm/drop_caches so it's not a surprise > that it happened. Processing dmesgs can work too but isn't particularly reliable or scalable. > BTW, counts of *events* don't really belong in meminfo. These really do > belong in /proc/vmstat if anything. Oh yeah, I don't have a strong opinion on where the counters should go. Thanks. -- tejun
