diff --git a/man5/proc.5 b/man5/proc.5
index ea937cf8c..259d17dd1 100644
--- a/man5/proc.5
+++ b/man5/proc.5
@@ -1894,7 +1894,8 @@ Page table entries size (since Linux 2.6.10).
 .IP *
 .IR VmSwap :
 .\" commit b084d4353ff99d824d3bc5a5c2c22c70b1fba722
-Swapped-out virtual memory size (since Linux 2.6.34).
+Swapped-out virtual memory size by anonymous private pages;
+shmem swap usage is not included (since Linux 2.6.34).
 .IP *
 .IR Threads :
 Number of threads in process containing this thread.