First push

qemu.d/cad/prepare/begin/alloc_hugepages.sh

@@ -0,0 +1,28 @@
+#!/bin/bash
+
+MEMORY=24576
+## Calculate number of hugepages to allocate from memory (in MB)
+HUGEPAGES="$(($MEMORY/$(($(grep Hugepagesize /proc/meminfo | awk '{print $2}')/1024))))"
+## Node to allocate on (node1 for this VM)
+NODESPATH=/sys/devices/system/node/node1
+
+echo "Allocating hugepages..."
+echo $HUGEPAGES > $NODESPATH/hugepages/hugepages-2048kB/nr_hugepages
+ALLOC_PAGES=$(cat $NODESPATH/hugepages/hugepages-2048kB/nr_hugepages)
+
+TRIES=0
+while (( $ALLOC_PAGES != $HUGEPAGES && $TRIES < 1000 ))
+do
+    echo 1 > /proc/sys/vm/compact_memory            ## defrag ram
+    echo $HUGEPAGES > $NODESPATH/hugepages/hugepages-2048kB/nr_hugepages
+    ALLOC_PAGES=$(cat $NODESPATH/hugepages/hugepages-2048kB/nr_hugepages)
+    echo "Succesfully allocated $ALLOC_PAGES / $HUGEPAGES"
+    let TRIES+=1
+done
+
+if [ "$ALLOC_PAGES" -ne "$HUGEPAGES" ]
+then
+    echo "Not able to allocate all hugepages. Reverting..."
+    echo 0 > $NODESPATH/hugepages/hugepages-2048kB/nr_hugepages
+    exit 1
+fi