From: Alan Cox This was on my TODO list for a while and it turns out someone already fixed the armwaving overcommit mode for the same problem. It is easy to get into a situation where you have no overcommit and nothing can be done because there is no memory to clean up the stable but non-useful state of the machine. The fix is trivial and duplicated from the armwaving overcommit code path. The last 3% of the memory can be claimed by root processes only. It isn't a cure but it does seem to solve the real world problems - at least providing you have enough memory for 3% to be useful 8). Signed-off-by: Andrew Morton --- 25-akpm/security/commoncap.c | 5 +++++ 1 files changed, 5 insertions(+) diff -puN security/commoncap.c~root-reservations-for-strict-overcommit security/commoncap.c --- 25/security/commoncap.c~root-reservations-for-strict-overcommit Tue Aug 31 16:50:27 2004 +++ 25-akpm/security/commoncap.c Tue Aug 31 16:50:27 2004 @@ -357,6 +357,11 @@ int cap_vm_enough_memory(long pages) allowed = (totalram_pages - hugetlb_total_pages()) * sysctl_overcommit_ratio / 100; + /* + * Leave the last 3% for root + */ + if (!capable(CAP_SYS_ADMIN)) + allowed -= allowed / 32; allowed += total_swap_pages; if (atomic_read(&vm_committed_space) < allowed) _