From 713edb8a99569f2f7e83790f7365916e04eb2594 Mon Sep 17 00:00:00 2001
From: Jared Still <jkstill@gmail.com>
Date: Mon, 18 Jul 2016 12:44:36 -0700
Subject: [PATCH] chk-anon-huge.sh prototype to check if Anonymous HugePages
 are configured and enabled

---
 chk-anon-huge.sh | 74 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100755 chk-anon-huge.sh

diff --git a/chk-anon-huge.sh b/chk-anon-huge.sh
new file mode 100755
index 0000000..066173b
--- /dev/null
+++ b/chk-anon-huge.sh
@@ -0,0 +1,74 @@
+#!/bin/bash
+
+function chkAnonHuge () {
+
+: <<'PYTHDOC'
+
+check for anonymous huge pages
+see Oracle Support Note:
+  ALERT: Disable Transparent HugePages on SLES11, RHEL6, RHEL7, OL6, OL7 and UEK2 Kernels (Doc ID 1557478.1)
+
+The note contains a recommendation to check /proc/meminfo as one method to detect Anonymous HugePages,
+but that method is only reliable if some Anonymous HugePages have actually been allocated.
+
+PYTHDOC
+
+	declare -a anonConfigFiles=(
+		[0]='/sys/kernel/mm/redhat_transparent_hugepage/enabled'
+		[1]='/sys/kernel/mm/transparent_hugepage/enabled'
+	)
+
+	fileCount=${#anonConfigFiles[@]}
+
+	i=0
+
+	anonFileToChk=''
+
+	while [[ $fileCount -gt $i ]]
+	do
+		#echo $i: ${anonConfigFiles[$i]}
+		[[ -r ${anonConfigFiles[$i]} ]] && {
+			anonFileToChk=${anonConfigFiles[$i]}
+			break
+		}
+		(( i++ ))
+	done
+
+	#echo anonFileToChk: $anonFileToChk
+
+: <<'ANONCHK'
+
+check the contents of file anonFileToChk
+
+'[always] never': Anonymous HugePages should be disabled.
+
+'always [never]': Anonymous HugePages are configured in the kernel, but disabled.
+
+If the file does not even exist, that Anonymous HugePages are not configured and can be ignored.
+
+ANONCHK
+
+	anonHugePagesConfigured=1
+	[[ -z $anonFileToChk ]] && anonHugePagesConfigured=0
+
+	#echo anonHugePagesConfigured: $anonHugePagesConfigured
+
+	anonHugePagesEnabled=0
+
+	if [[ $anonHugePagesConfigured -gt 0 ]]; then
+		grep '[always]' $anonFileToChk >/dev/null && {
+			#echo anonymous HugePages are enabled
+			anonHugePagesEnabled=1
+		}
+	fi
+
+	# return code - will be either 0 or 1
+	echo $(( anonHugePagesConfigured * anonHugePagesEnabled ))
+
+}
+
+r=$(chkAnonHuge)
+
+echo "r: $r"
+
+