CLOUDSTACK-9929: Do not gather statistics for CDROM or FLOPPY devices

Libvirt / Qemu (KVM) does not collect statistics about these either.

On some systems it might even yield a 'internal error' from libvirt
when attempting to gather block statistics from such devices.

For example Ubuntu 16.04 (Xenial) has a issue with this.

Skip them when looping through all devices.

Signed-off-by: Wido den Hollander <wido@widodh.nl>

Author: wido

plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java

@@ -3095,6 +3095,9 @@ public VmStatsEntry getVmStat(final Connect conn, final String vmName) throws Li
             long bytes_rd = 0;
             long bytes_wr = 0;
             for (final DiskDef disk : disks) {
+                if (disk.getDeviceType() == DeviceType.CDROM || disk.getDeviceType() == DeviceType.FLOPPY) {
+                    continue;
+                }
                 final DomainBlockStats blockStats = dm.blockStats(disk.getDiskLabel());
                 io_rd += blockStats.rd_req;
                 io_wr += blockStats.wr_req;