On Wed, Apr 27, 2022 at 11:36:54AM -0700, Andrew Morton wrote: > On Wed, 27 Apr 2022 12:00:15 -0400 Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > > > Currently it requires poking at debugfs to figure out the size and > > population of the zswap cache on a host. There are no counters for > > reads and writes against the cache. As a result, it's difficult to > > understand zswap behavior on production systems. > > > > Print zswap memory consumption and how many pages are zswapped out in > > /proc/meminfo. Count zswapouts and zswapins in /proc/vmstat. > > /proc/meminfo is rather prime real estate. Is this important enough to > be placed in there, or should it instead be in the more lowly > /proc/vmstat? The zswap pool size is capped to 20% of available RAM, and we usually have a utilization of tens of gigabytes. I think it's fair to say it's a first class memory consumer when enabled, and actually a huge hole in /proc/meminfo coverage right now. > /proc/meminfo is documented in Documentation/filesystems/proc.rst ;) > > That file appears to need a bit of updating for other things. "The following is from a 16GB PIII, which has highmem enabled." lmao. I'll send a general update for that, and a delta fixlet for 4/5. Thanks!
