Added options "discard=unmap,detect-zeroes=unmap" to QEMU in order to handle...

Added options "discard=unmap,detect-zeroes=unmap" to QEMU in order to handle sparse files to save disk space.
Updated template_creator, update_disk and vm_run scripts in consequence.

README.md

@@ -567,7 +567,7 @@ The `vm_run` script, located in `/usr/local/nexus-server/bin/`, is a convenience
 vm_run - launch a VM on the specified disk image(s).
 The VM is configured with 4 CPUs and 4G of RAM.
 
-Usage: vm_run -d disk -c iso
+Usage: vm_run -d disk -i iso
 disk    the disk image to use (typically a .qcow file)
 iso     the CD/DVD-ROM image to use (typically an .iso file)
 

src/command/QemuSystem.go

@@ -57,7 +57,7 @@ func NewQemuSystem(qgaSock string, cpus int, ram int, nic string, diskFile strin
 	//   - In the guest: mkdir shared && sudo mount -t 9p sharedfs shared
 	// 4) For QEMU Guest Agent support:
 	//  -device virtio-serial -device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 -chardev socket,path=path_to_sock_file,server=on,wait=off,id=qga0
-	cmd := exec.Command(qemusystemBinary, "-enable-kvm", "-cpu", "host", "-smp", "cpus="+strconv.Itoa(cpus), "-m", strconv.Itoa(ram), "-drive", "file="+diskFile+",index=0,media=disk,format=qcow2,if=virtio", "-vga", "virtio", "-device", "virtio-serial-pci", "-object", "secret,id=sec,file="+secretPwdFile+",format=base64", "-spice", "tls-port="+strconv.Itoa(spicePort)+",password-secret=sec,x509-dir="+certDir, "-device", "virtserialport,chardev=spicechannel0,name=com.redhat.spice.0", "-chardev", "spicevmc,id=spicechannel0,name=vdagent", "-nic", nicArgs, "-device", "virtio-serial", "-device", "virtserialport,chardev=qga0,name=org.qemu.guest_agent.0", "-chardev", "socket,path="+qgaSock+",server=on,wait=off,id=qga0")
+	cmd := exec.Command(qemusystemBinary, "-enable-kvm", "-cpu", "host", "-smp", "cpus="+strconv.Itoa(cpus), "-m", strconv.Itoa(ram), "-drive", "file="+diskFile+",index=0,media=disk,format=qcow2,discard=unmap,detect-zeroes=unmap,if=virtio", "-vga", "virtio", "-device", "virtio-serial-pci", "-object", "secret,id=sec,file="+secretPwdFile+",format=base64", "-spice", "tls-port="+strconv.Itoa(spicePort)+",password-secret=sec,x509-dir="+certDir, "-device", "virtserialport,chardev=spicechannel0,name=com.redhat.spice.0", "-chardev", "spicevmc,id=spicechannel0,name=vdagent", "-nic", nicArgs, "-device", "virtio-serial", "-device", "virtserialport,chardev=qga0,name=org.qemu.guest_agent.0", "-chardev", "socket,path="+qgaSock+",server=on,wait=off,id=qga0")
 
 	return cmd, nil
 }

tools/template_creator

@@ -18,7 +18,7 @@ function create_disk {
 # Args: id, cpus, ram, disk, iso
 function run_qemu {
     dir=$1
-    qemu-system-x86_64 -enable-kvm -cpu host -smp cpus=$2 -m $3 -drive file=$dir/$4,index=0,media=disk,format=qcow2,if=virtio -vga virtio -device virtio-serial-pci -nic user,model=virtio-net-pci -drive file=$5,index=1,media=cdrom,format=raw,read-only=on || { rm -rf $dir ; exit 1 ; }
+    qemu-system-x86_64 -enable-kvm -cpu host -smp cpus=$2 -m $3 -drive file=$dir/$4,index=0,media=disk,format=qcow2,discard=unmap,detect-zeroes=unmap,if=virtio -vga virtio -device virtio-serial-pci -nic user,model=virtio-net-pci -drive file=$5,index=1,media=cdrom,format=raw,read-only=on || { rm -rf $dir ; exit 1 ; }
 }
 
 # Args: id, name, owner, visibility

tools/update_disk

@@ -25,4 +25,4 @@ if ! [ -f $DISK ]; then
     exit 1
 fi
 
-qemu-system-x86_64 -enable-kvm -cpu host -smp cpus=$CPU -m $RAM -drive file=$DISK,index=0,media=disk,format=qcow2,if=virtio -vga virtio -device virtio-serial-pci -nic user,model=virtio-net-pci
+qemu-system-x86_64 -enable-kvm -cpu host -smp cpus=$CPU -m $RAM -drive file=$DISK,index=0,media=disk,format=qcow2,discard=unmap,detect-zeroes=unmap,if=virtio -vga virtio -device virtio-serial-pci -nic user,model=virtio-net-pci

tools/vm_run

@@ -13,7 +13,7 @@ function usage {
 	echoerr "$APP - launch a VM on the specified disk image(s)."
 	echoerr "The VM is configured with $CPUS CPUs and $RAM of RAM."
     echoerr ""
-    echoerr "Usage: $APP -d disk -c iso"
+    echoerr "Usage: $APP -d disk -i iso"
     echoerr "disk    the disk image to use (typically a .qcow file)"
     echoerr "iso     the CD/DVD-ROM image to use (typically an .iso file)"
     echoerr ""
@@ -32,7 +32,7 @@ while [[ $# -gt 0 ]]; do
       shift # past argument
       shift # past value
       ;;
-    -c)
+    -i)
       iso="$2"
       shift # past argument
       shift # past value
@@ -45,7 +45,7 @@ while [[ $# -gt 0 ]]; do
 done
 
 if [ ! -z $disk ]; then
-    disk_drive="-drive file=$disk,index=0,media=disk,format=qcow2,if=virtio"
+    disk_drive="-drive file=$disk,index=0,media=disk,format=qcow2,discard=unmap,detect-zeroes=unmap,if=virtio"
 fi
 
 if [ ! -z $iso ]; then