Milind Changire reported that GlusterFS fails to build on RHEL5 because linux/oom.h is unavailable. Milind's initial patch disables OOM adjustment completely for those environments that do not have this header. However, I'd take another approach that: 1) checks for linux/oom.h in compile-time and defines necessary constants if the header is not present; 2) checks for available OOM API in /proc in run-time and uses it accordingly. This allows OOM to be adjusted properly on RHEL5 (the kernel is pretty new to present /proc API for that) as well as RHEL6 (the kernel has many thing backported including new /proc API). Change-Id: I1bc610586872d208430575c149a7d0c54bd82370 BUG: 1379769 Signed-off-by: Oleksandr Natalenko <onatalen@redhat.com> Reviewed-on: http://review.gluster.org/15587 Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Reviewed-by: Niels de Vos <ndevos@redhat.com> Smoke: Gluster Build System <jenkins@build.gluster.org> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org> CentOS-regression: Gluster Build System <jenkins@build.gluster.org>