docs: proc.rst: meminfo: briefly describe gaps in memory accounting

Add a paragraph that explains that it may happen that the counters in
/proc/meminfo do not add up to the overall memory usage.

Link: https://lkml.kernel.org/r/20210421061127.1182723-1-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mike Rapoport 2021-06-30 18:50:00 -07:00 committed by Linus Torvalds
parent 781eb2cdd2
commit 8d719afcb3

View File

@ -933,8 +933,15 @@ meminfo
~~~~~~~
Provides information about distribution and utilization of memory. This
varies by architecture and compile options. The following is from a
16GB PIII, which has highmem enabled. You may not have all of these fields.
varies by architecture and compile options. Some of the counters reported
here overlap. The memory reported by the non overlapping counters may not
add up to the overall memory usage and the difference for some workloads
can be substantial. In many cases there are other means to find out
additional memory using subsystem specific interfaces, for instance
/proc/net/sockstat for TCP memory allocations.
The following is from a 16GB PIII, which has highmem enabled.
You may not have all of these fields.
::