Verifying The Para-Virtualized Drivers Have Successfully Loaded; The System Has Limited Throughput With Para-Virtualized Drivers - Red Hat ENTERPRISE LINUX 5 - VIRTUALIZATION GUIDE Manual

Chapter 35. Troubleshooting the Xen para-virtualized drivers
35.5. Verifying the para-virtualized drivers have
successfully loaded
One of the first tasks you will want to do is to verify that the drivers have actually been loaded into your
system.
After the para-virtualized drivers have been installed and the guest has been rebooted you can verify
that the drivers have loaded. First you should confirm the drivers have logged their loading into /var/
log/messages
# grep --E -"vif|vbd|xen" -/var/log/messages
xen_mem: Initialising balloon driver
vif vif-0: 2 parsing device/vif/0/mac
vbd vbd-768: 19 xlvbd_add at -/local/domain/0/backend/vbd/21/76
vbd vbd-768: 19 xlvbd_add at -/local/domain/0/backend/vbd/21/76
xen-vbd: registered block device major 202
You can also use the lsmod command to list the loaded para-virtualized drivers. It should output a list
containing the xen_vnif, xen_vbd, xen_platform_pci and xen_balloon modules.
# lsmod|grep xen
xen_vbd
xen_vnif
xen_balloon
xen_platform_pci
35.6. The system has limited throughput with para-
virtualized drivers
If network throughput is still limited even after installing the para-virtualized drivers and you have
confirmed they are loaded correctly (refer to
successfully loaded"). To fix this problem, remove the 'type=ioemu' part of 'vif=' line in your guest's
configuration file.
372
19168 1
28416 0
15256 1 xen_vnif
98520 3 xen_vbd,xen_vnif,xen_balloon,[permanent]
Section 35.5, "Verifying the para-virtualized drivers have