From a195cf013e98b02d3c129e2cccd7efa98aabf546 Mon Sep 17 00:00:00 2001 From: Brian Masney Date: Thu, 28 May 2026 09:45:10 -0400 Subject: docs: mm: clarify that user_reserve_kbytes has no effect when overcommit_memory is set to 0 or 1 Looking at __vm_enough_memory() in mm/util.c, user_reserve_kbytes has no effect when overcommit_memory is set to 0 or 1. The documentation for overcommit_memory already references user_reserve_kbytes when the flag is set to 2. Let's go ahead and add a clarification to user_reserve_kbytes in vm.rst that it has no effect when overcommit_memory is set to 0 or 1. Link: https://lore.kernel.org/20260528-mm-clarify-docs-v1-1-aa88e83b4bfd@redhat.com Signed-off-by: Brian Masney Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- Documentation/admin-guide/sysctl/vm.rst | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation/admin-guide/sysctl') diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst index 97e12359775c..b9b0c218bfb4 100644 --- a/Documentation/admin-guide/sysctl/vm.rst +++ b/Documentation/admin-guide/sysctl/vm.rst @@ -1034,6 +1034,8 @@ min(3% of current process size, user_reserve_kbytes) of free memory. This is intended to prevent a user from starting a single memory hogging process, such that they cannot recover (kill the hog). +This setting has no effect when overcommit_memory is set to 0 or 1. + user_reserve_kbytes defaults to min(3% of the current process size, 128MB). If this is reduced to zero, then the user will be allowed to allocate -- cgit v1.2.3