Re: [PATCH 4/5] mm: zswap: add basic meminfo and vmstat coverage

From: Andrew Morton
Date: Wed Apr 27 2022 - 14:48:46 EST


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?

/proc/meminfo is documented in Documentation/filesystems/proc.rst ;)

That file appears to need a bit of updating for other things.