From 8d719afcb34434ebfa7911338d8c777eca8452b0 Mon Sep 17 00:00:00 2001 From: Mike Rapoport Date: Wed, 30 Jun 2021 18:50:00 -0700 Subject: 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 Acked-by: Michal Hocko Reviewed-by: Matthew Wilcox (Oracle) Acked-by: Vlastimil Babka Cc: Jonathan Corbet Cc: Alexey Dobriyan Cc: Eric Dumazet Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.rst | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst index 81bfe3c800cc..dd4e3e18c22b 100644 --- a/Documentation/filesystems/proc.rst +++ b/Documentation/filesystems/proc.rst @@ -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. :: -- cgit v1.2.3