todarsey Posted August 7, 2009 Share Posted August 7, 2009 Not sure if this belongs here or in the networking section. I currently running Win Server 08 x64 SP2 1 NIC. I have running inside of it a Windows XP VM SP2 via Hyper-V. The issue I am having is, it is taking 4-6 seconds to copy a 10MB file from the VM to the server. I have tried both legacy network adapters and regular network adapters. I am only having this issue with the VM's all other computers can copy data to the server atleast 60MB/s. Any ideas? Link to comment Share on other sites More sharing options...
fizban2 Posted August 7, 2009 Share Posted August 7, 2009 could be in issue with the NIC being shared by both machines. can you add another NIC specifically for the VM's and leave the other NIC for the Hyper-V server it self Link to comment Share on other sites More sharing options...
todarsey Posted August 7, 2009 Author Share Posted August 7, 2009 I'll give it a shot. Link to comment Share on other sites More sharing options...
CoffeeFiend Posted August 7, 2009 Share Posted August 7, 2009 Try disabling TCP checksum offloading. I bet that'll do the trick. Link to comment Share on other sites More sharing options...
todarsey Posted August 7, 2009 Author Share Posted August 7, 2009 could be in issue with the NIC being shared by both machines. can you add another NIC specifically for the VM's and leave the other NIC for the Hyper-V server it selfNope, that didn't work. Link to comment Share on other sites More sharing options...
todarsey Posted August 7, 2009 Author Share Posted August 7, 2009 Try disabling TCP checksum offloading. I bet that'll do the trick.That didn't work either. I have disabled TCP checksum offloading and TCP Large Send Offload on both NIC's. Link to comment Share on other sites More sharing options...
CoffeeFiend Posted August 7, 2009 Share Posted August 7, 2009 That didn't work either. I have disabled TCP checksum offloading and TCP Large Send Offload on both NIC's.You're not alone having that problem, and normally disabling offloading fixes it. I'd make sure it's also disabled in the VMs. Link to comment Share on other sites More sharing options...
Mr Snrub Posted August 7, 2009 Share Posted August 7, 2009 I currently running Win Server 08 x64 SP2 1 NIC. I have running inside of it a Windows XP VM SP2 via Hyper-V. The issue I am having is, it is taking 4-6 seconds to copy a 10MB file from the VM to the server.Do you have the Integration Services installed in the VM? (I am assuming yes, if you got the synthetic NIC to work.)Did you install the Hyper-V RTM bits before adding the Hyper-V role? (KB950050)What if you use a Private network instead of an External one, do you get the same kind of throughput between the child and parent partitions?What about SMB transfer speeds from the VM to physical machines on the LAN, other than the host?Any reason you're not using SP3 on the XP VM?Are there any other VMs on this host that you can use for testing, maybe with other versions of Windows?I have tried both legacy network adapters and regular network adapters.Synthetic ("regular") network adapters are preferred.I am only having this issue with the VM's all other computers can copy data to the server atleast 60MB/s.Elaborate here a bit, just to clarify - are you talking about other VMs on the same host, or other VMs on a differnet host, or physical machines on the LAN? What version of Windows work for the other machines?You could test setting TcpAckFrequency to 1 on the XP machine and rebooting:KB328890 Link to comment Share on other sites More sharing options...
todarsey Posted August 7, 2009 Author Share Posted August 7, 2009 "Do you have the Integration Services installed in the VM? (I am assuming yes, if you got the synthetic NIC to work.)" - yes"Did you install the Hyper-V RTM bits before adding the Hyper-V role? (KB950050)" - no"What about SMB transfer speeds from the VM to physical machines on the LAN, other than the host?" about the same to other physical machines."Any reason you're not using SP3 on the XP VM?" Not really, just haven't installed it yet. I will try that."Are there any other VMs on this host that you can use for testing, maybe with other versions of Windows?" - yes, 3 total. Using LAN Speed Test and a 10MB file copying to the same place on the server, one is another XP machine with SP3 with a transfer speed of 16.55Mbps. Another is a WHS machine with a ransfer speed of 31.40Mbps. The last one is Win XP SP2 with a transfer speed of 7.07Mbps. A test using a physical computer gets 81.13Mbps."You could test setting TcpAckFrequency to 1 on the XP machine and rebooting: KB328890" Does this apply to server 08 as well? It only says for server 03. Do I do it on both server ans vm? Link to comment Share on other sites More sharing options...
Mr Snrub Posted August 8, 2009 Share Posted August 8, 2009 "Did you install the Hyper-V RTM bits before adding the Hyper-V role? (KB950050)" - noYipes - okay when you installed the Hyper-V role, you added the beta bits and Integration Services (as the host is currently running SP1, the release version).To be honest, I would do the following in your situation:- delete or merge all snapshots on all VMs- uninstall the Integrations Services on all VMs- shut down (not save) all VMs- remove the Hyper-V role from the host and reboot- apply Windows Server 2008 x64 SP2- add the Hyper-V role (which will now no longer be beta and have several hotfixes included)- start the VMs and add the Integration Services"Any reason you're not using SP3 on the XP VM?" Not really, just haven't installed it yet. I will try that.When setting up a new environment, I would always start at the latest SP level for each OS - service packs often contain more than just the hotfix packages which exist on Windows Updates or can be found through KB articles.5.1 kernel (XP): SP35.2 kernel (W2K3, XP x64): SP26.0 kernel (Vista, W2K8): SP2"You could test setting TcpAckFrequency to 1 on the XP machine and rebooting: KB328890" Does this apply to server 08 as well? It only says for server 03. Do I do it on both server ans vm?The networking stack was written from the ground up on Vista, so I'd leave it for now as you know other physical machines can communicate with the same server through the same NIC at a reasonable speed.If you're running AV on the host, also make sure that the folders related to Hyper-V are excluded from scanning, it can also be worth testing with AV removed (not just disabled) to see if it has any effect on the throughput.Is the throughput the same in either direction between the VMs and the host? Link to comment Share on other sites More sharing options...
todarsey Posted August 8, 2009 Author Share Posted August 8, 2009 "apply Windows Server 2008 x64 SP2" - it already has SP2 on it. Do I need to uninstall and reinstall SP2 after I remove the hyper-v role? Will removing SP2 have any effect on my other installed roles? - AD, DNS, DHCP, File Server anf Hyper-V are all of the roles installed. Link to comment Share on other sites More sharing options...
cluberti Posted August 8, 2009 Share Posted August 8, 2009 "apply Windows Server 2008 x64 SP2" - it already has SP2 on it. Do I need to uninstall and reinstall SP2 after I remove the hyper-v role? Will removing SP2 have any effect on my other installed roles? - AD, DNS, DHCP, File Server anf Hyper-V are all of the roles installed.If you've upgraded it to SP2, the role was upgraded, so there's no need to remove and re-add it. However, you really do need to do the rest (remove ICs, shut VMs down, merge snapshots, bring them up, and re-install the ICs). You have the Hyper-V beta integration components installed in your VMs running on the SP2 Hyper-V, which is known to cause problems (I know this, because you cannot install the Hyper-V RTM or SP2 IC bits in an XPSP2 guest, but you could with beta, so if you've got ICs there I know that you've got the beta bits installed in your guest OSes). Link to comment Share on other sites More sharing options...
Mr Snrub Posted August 8, 2009 Share Posted August 8, 2009 "apply Windows Server 2008 x64 SP2" - it already has SP2 on it. Do I need to uninstall and reinstall SP2 after I remove the hyper-v role? Will removing SP2 have any effect on my other installed roles? - AD, DNS, DHCP, File Server anf Hyper-V are all of the roles installed.Ack, sorry I read the original post as SP1 for some reason - as cluberti says there's no need to remove or reinstall SP2, just clean up & service pack the VMs.[it's preferred to use the host for only the Hyper-V role btw, if this is just a dev environment then no worries.] Link to comment Share on other sites More sharing options...
todarsey Posted August 8, 2009 Author Share Posted August 8, 2009 (edited) Well, I have uninstalled Hyper-V Guest Components on all VMs and then reinstalled. The only one that had an increase in speed was the WHS VM. Could the issue be that the other VMs were once physical machines and I took an image of those and created the VMs? The WHS VM now gets a little over 100Mbps. Edited August 9, 2009 by todarsey Link to comment Share on other sites More sharing options...
Mr Snrub Posted August 9, 2009 Share Posted August 9, 2009 Physical machines you "took an image of" - can you talk us through how you achieved this?Tools like SCVMM have P2V components to install an agent on physical machines and migrate them into Hyper-V, stripping out device drivers and replacing them with virtual ones compatible with the target host, but I'm guessing you didn't use this as the System Center suite isn't free.I guess the easiest way to verify if it was that process would be to set up an identical VM from scratch and do a clean install of XP SP3 & the Integration Services, then compare how it performs... Link to comment Share on other sites More sharing options...
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