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+==================
+HugeTLB Controller
+==================
+
+The HugeTLB controller allows to limit the HugeTLB usage per control group and
+enforces the controller limit during page fault. Since HugeTLB doesn't
+support page reclaim, enforcing the limit at page fault time implies that,
+the application will get SIGBUS signal if it tries to access HugeTLB pages
+beyond its limit. This requires the application to know beforehand how much
+HugeTLB pages it would require for its use.
+
+HugeTLB controller can be created by first mounting the cgroup filesystem.
+
+# mount -t cgroup -o hugetlb none /sys/fs/cgroup
+
+With the above step, the initial or the parent HugeTLB group becomes
+visible at /sys/fs/cgroup. At bootup, this group includes all the tasks in
+the system. /sys/fs/cgroup/tasks lists the tasks in this cgroup.
+
+New groups can be created under the parent group /sys/fs/cgroup::
+
+  # cd /sys/fs/cgroup
+  # mkdir g1
+  # echo $$ > g1/tasks
+
+The above steps create a new group g1 and move the current shell
+process (bash) into it.
+
+Brief summary of control files::
+
+ hugetlb.<hugepagesize>.limit_in_bytes     # set/show limit of "hugepagesize" hugetlb usage
+ hugetlb.<hugepagesize>.max_usage_in_bytes # show max "hugepagesize" hugetlb  usage recorded
+ hugetlb.<hugepagesize>.usage_in_bytes     # show current usage for "hugepagesize" hugetlb
+ hugetlb.<hugepagesize>.failcnt            # show the number of allocation failure due to HugeTLB limit
+
+For a system supporting three hugepage sizes (64k, 32M and 1G), the control
+files include::
+
+  hugetlb.1GB.limit_in_bytes
+  hugetlb.1GB.max_usage_in_bytes
+  hugetlb.1GB.usage_in_bytes
+  hugetlb.1GB.failcnt
+  hugetlb.64KB.limit_in_bytes
+  hugetlb.64KB.max_usage_in_bytes
+  hugetlb.64KB.usage_in_bytes
+  hugetlb.64KB.failcnt
+  hugetlb.32MB.limit_in_bytes
+  hugetlb.32MB.max_usage_in_bytes
+  hugetlb.32MB.usage_in_bytes
+  hugetlb.32MB.failcnt