diff options
| -rw-r--r-- | Documentation/sysctl/vm.txt | 23 | ||||
| -rw-r--r-- | mm/oom_kill.c | 3 |
2 files changed, 20 insertions, 6 deletions
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index e96a341eb7e..1d192565e18 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -197,11 +197,22 @@ and may not be fast. panic_on_oom -This enables or disables panic on out-of-memory feature. If this is set to 1, -the kernel panics when out-of-memory happens. If this is set to 0, the kernel -will kill some rogue process, called oom_killer. Usually, oom_killer can kill -rogue processes and system will survive. If you want to panic the system -rather than killing rogue processes, set this to 1. +This enables or disables panic on out-of-memory feature. -The default value is 0. +If this is set to 0, the kernel will kill some rogue process, +called oom_killer. Usually, oom_killer can kill rogue processes and +system will survive. + +If this is set to 1, the kernel panics when out-of-memory happens. +However, if a process limits using nodes by mempolicy/cpusets, +and those nodes become memory exhaustion status, one process +may be killed by oom-killer. No panic occurs in this case. +Because other nodes' memory may be free. This means system total status +may be not fatal yet. +If this is set to 2, the kernel panics compulsorily even on the +above-mentioned. + +The default value is 0. +1 and 2 are for failover of clustering. Please select either +according to your policy of failover. diff --git a/mm/oom_kill.c b/mm/oom_kill.c index a35e7a8ebd7..038d2234f13 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -413,6 +413,9 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order) show_mem(); } + if (sysctl_panic_on_oom == 2) + panic("out of memory. Compulsory panic_on_oom is selected.\n"); + cpuset_lock(); read_lock(&tasklist_lock); |