Performance issue Xen vm

I have setup up a DSS V6 lite server as a VM on a Xenserver 5.6 host. The volume assigned to the DSS server is local to the host and is part of a hardware raid5 on the Dell 2950 server.

I've set up a nas share and it works as expected tied into our AD with the exception that throughput is very slow. Copying files to or from the device max out at 6 MBps.

I have a windows 2008 VM on the same host and copying files to and from it average 86MBps.

There is only one NIC assigned to both vms (the same NIC) and everything else is shared as well, so I don't think it is a hardware issue. My guess is that it is the NIC driver on the DSS server, but have no idea how to test it.

Are there any good whitepapers or documentation on troubleshooting performance issues?

Can you download the log from the GUI in Status > Hardware > Log then click on the Download button then use a WinRAR or other program to view the log file and look for the test.log and search the "hdparm" and check the speed of the volume in the form of "sda or other" and also look for "ifconfig -a" to check the speed of the nics to make sure they are at 1000Mb/s and if there are any dropped packets.

Thanks for the great info.

The hd performance looks ok at 58Mb, but the NIC is showing 100Mb and has dropped packets. So I think I need to change nic or driver settings. From the documentation, it looks like that has to be done via the console, is there a way to send the ctrl-alt key via xencenter?

Ok, I've figured out how to get into the console settings, but could not find anything obvious to change.

Open-e shows the NIC as a Realtek Rtl-8139 running 100Mb Full duplex.

The physical nic in the xen server is a broadcom NetXtreme II BCM5708.

Any suggestions on what to change?

Probably you need to change ethernet card in XenServer.

That won't be possible in this server, the slots are full. Also, I'm not sure that would help since I think Xen would be virtualizing nic from the open-e pov.

Does the full version support alerternate drivers or is there a driver available like the xen-tools provides?

Quote:

---

Originally Posted by szohn

Ok, I've figured out how to get into the console settings, but could not find anything obvious to change.

Open-e shows the NIC as a Realtek Rtl-8139 running 100Mb Full duplex.

The physical nic in the xen server is a broadcom NetXtreme II BCM5708.

Any suggestions on what to change?

---

Is this Realtek Rtl-8139 a 10/100MB NIC? See link below to confirm.

http://en.wikipedia.org/wiki/RTL8139

Keep in mind this a virtual instance of DSS on a Xen host.

DSS is seeing the NIC provided by the host as a realtek adapter. The physical NIC on the host it a 1Gbit broadcom adapter and can be seen by other vms as gigabit adapters.

Can you test with the trial version of the DSS V6.

I reinstalled and there was no difference. Further research leads me to believe the only solution is a pv driver for the nic. I tried a couple other nas type appliances with similar issues.

Thanks for your help.

Quote:

---

Originally Posted by szohn

That won't be possible in this server, the slots are full. Also, I'm not sure that would help since I think Xen would be virtualizing nic from the open-e pov.

---

I don't mean change ethernet card in server, I mean change ethenet card in configuration.
In pure xen you just add to vif definition 'model=e1000' in configuration file. I do not know how to do this in XenServer.