Documentation/sysctl/kernel.txt: document /proc/sys/shmall

Signed-off-by: Carlos Alberto Lopez Perez <clopez@igalia.com>
Cc: Rob Landley <rob@landley.net>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 51b953a1b149..ccd42589e124 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -561,6 +561,19 @@ are doing anyway :)
 
 ==============================================================
 
+shmall:
+
+This parameter sets the total amount of shared memory pages that
+can be used system wide. Hence, SHMALL should always be at least
+ceil(shmmax/PAGE_SIZE).
+
+If you are not sure what the default PAGE_SIZE is on your Linux
+system, you can run the following command:
+
+# getconf PAGE_SIZE
+
+==============================================================
+
 shmmax:
 
 This value can be used to query and set the run time limit