[PATCH] docs: admin-guide: Fix default value of max_map_count in sysctl/vm.rst

[PATCH] docs: admin-guide: Fix default value of max_map_count in sysctl/vm.rst

[Fengfei Xi]

Since the default value of sysctl_max_map_count is defined as
DEFAULT_MAX_MAP_COUNT from mm/util.c

    int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;

DEFAULT_MAX_MAP_COUNT is defined as 65530 (65535-5) in include/linux/mm.h

    #define MAPCOUNT_ELF_CORE_MARGIN        (5)
    #define DEFAULT_MAX_MAP_COUNT   (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)

Signed-off-by: Fengfei Xi <xi.fengfei@h3c.com>
---
 Documentation/admin-guide/sysctl/vm.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst
index f455fa00c..834c3fc74 100644
--- a/Documentation/admin-guide/sysctl/vm.rst
+++ b/Documentation/admin-guide/sysctl/vm.rst
@@ -428,7 +428,7 @@ While most applications need less than a thousand maps, certain
 programs, particularly malloc debuggers, may consume lots of them,
 e.g., up to one or two maps per allocation.
 
-The default value is 65536.
+The default value is 65530.
 
 
 memory_failure_early_kill:
-- 
2.17.1

Re: [PATCH] docs: admin-guide: Fix default value of max_map_count in sysctl/vm.rst

[Jonathan Corbet]

On Thu, 10 Dec 2020 16:21:34 +0800
Fengfei Xi <xi.fengfei@h3c.com> wrote:

> Since the default value of sysctl_max_map_count is defined as
> DEFAULT_MAX_MAP_COUNT from mm/util.c
> 
>     int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;
> 
> DEFAULT_MAX_MAP_COUNT is defined as 65530 (65535-5) in include/linux/mm.h
> 
>     #define MAPCOUNT_ELF_CORE_MARGIN        (5)
>     #define DEFAULT_MAX_MAP_COUNT   (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
> 
> Signed-off-by: Fengfei Xi <xi.fengfei@h3c.com>
> ---
>  Documentation/admin-guide/sysctl/vm.rst | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst
> index f455fa00c..834c3fc74 100644
> --- a/Documentation/admin-guide/sysctl/vm.rst
> +++ b/Documentation/admin-guide/sysctl/vm.rst
> @@ -428,7 +428,7 @@ While most applications need less than a thousand maps, certain
>  programs, particularly malloc debuggers, may consume lots of them,
>  e.g., up to one or two maps per allocation.
>  
> -The default value is 65536.
> +The default value is 65530.

Applied, thanks.

jon