Run lvs only one time

Also make the case esac readable

kvmstats.sh

@@ -40,6 +40,9 @@ do
 done
 
 TMPFILE=$(tempfile)
+LVSOUT=$(tempfile)
+
+lvs --units b --nosuffix >$LVSOUT
 
 for VM in $(virsh list --all --name)
 do
@@ -48,9 +51,14 @@ do
     for DEV in $(hxselect -s'\n' 'domain devices disk[device=disk] source' </etc/libvirt/qemu/$VM.xml | cut -d\" -f2)
     do
         case $DEV in
-        /dev/drbd/*) DISK=$(lvs --units b --nosuffix | awk "/$VM/ { ans += \$NF } END { print ans / 1024^3 }") ;;
-        *.qcow2)     DISK=$(du -sBG $DEV |  awk '{ print substr($1, 0, length($1) - 1) }') ;;
-        *)           DISK=0;;
+        /dev/drbd/*)
+		DISK=$(cat $LVSOUT | awk "/$VM/ { ans += \$NF } END { print ans / 1024 ^ 3 }")
+		;;
+        *.qcow2)
+		DISK=$(du -sBG $DEV | awk '{ print substr($1, 0, length($1) - 1) }')
+		;;
+        *)
+		DISK=0
         esac
     done
     echo $VM $VCPU $RAM $DISK
@@ -62,4 +70,4 @@ done >$TMPFILE
     awk '{ vcpu += $2; ram += $3; disk += $4 } END { print "TOTAL", vcpu, ram, disk }' <$TMPFILE
 ) | column -t
 
-rm $TMPFILE
+rm $TMPFILE $LVSOUT