Sounds like you are referring to the issue where RSS Scaling is enabled, which by default is disabled on individual Windows NICs. I believe all the problem does is make the performance the same as if didn't have RSS Scaling enabled. In any case, VMware just came out with a new version of the Tools that resolves the issue.
Even if your VM is not being affected, you may want to get the new version of the Tools, install them and set RSS Scaling on the NIC. It's supposed to make a big performance difference, though obviously any other issues you have may override that. Still probably worth trying. I've just begun to do that on servers where app owners say they need better network performance and so far I've only been able to do 2 or 3 due to the required reboot. -----Original Message----- From: listsad...@lists.myitforum.com [mailto:listsad...@lists.myitforum.com] On Behalf Of Jack Kramer Sent: Friday, May 26, 2017 11:53 PM To: ntsysadm@lists.myitforum.com Subject: Re: [NTSysADM] Very strange problem file server - read vs. write VMXNET3 adapter? There's a bug I'm halfway remembering with the paravirtualized driver, 10.x tools branch, and multi-core guest VMs. Perhaps you're running into that? Sent from my iPhone > On May 26, 2017, at 7:10 PM, Kurt Buff <kurt.b...@gmail.com> wrote: > > I'm on the phone with MSFT now. > > I'll update y'all once I know more. > > Kurt > >> On Fri, May 26, 2017 at 3:54 PM, Michael B. Smith <mich...@smithcons.com> wrote: >> Time for netmon/wireshark. >> >> -----Original Message----- >> From: listsad...@lists.myitforum.com >> [mailto:listsad...@lists.myitforum.com] On Behalf Of Kurt Buff >> Sent: Friday, May 26, 2017 6:09 PM >> To: ntsysadm >> Subject: Re: [NTSysADM] Very strange problem file server - read vs. >> write >> >> Multiple workstations. I've migrated the file server to different hosts (5 in the cluster), and it doesn't seem to make a difference. >> >> Kurt >> >>> On Fri, May 26, 2017 at 2:17 PM, elsalvoz <elsal...@gmail.com> wrote: >>> One, multiple or all workstations? How about server on different >>> host or physicals? >>> >>> Cesar A. >>> >>>> On May 26, 2017 2:10 PM, "Michael B. Smith" <mich...@smithcons.com> wrote: >>>> >>>> Without a trace I can't be sure. But it seems likely. >>>> >>>> Have you also verified that the link is negotiating to the highest >>>> speed available and that it is error free? >>>> >>>> -----Original Message----- >>>> From: listsad...@lists.myitforum.com >>>> [mailto:listsad...@lists.myitforum.com] On Behalf Of Kurt Buff >>>> Sent: Friday, May 26, 2017 4:04 PM >>>> To: ntsysadm >>>> Subject: Re: [NTSysADM] Very strange problem file server - read vs. >>>> write >>>> >>>> No, we have not. It's required for some older machines. >>>> >>>> FWIW, the client's I'm testing with are Win10 1607. >>>> >>>> I presume that your implication is that turning it off would speed >>>> things up? >>>> >>>> Kurt >>>> >>>> On Fri, May 26, 2017 at 12:33 PM, Michael B. Smith >>>> <mich...@smithcons.com> >>>> wrote: >>>>> Have you disabled smb1? >>>>> >>>>> -----Original Message----- >>>>> From: listsad...@lists.myitforum.com >>>>> [mailto:listsad...@lists.myitforum.com] On Behalf Of Kurt Buff >>>>> Sent: Friday, May 26, 2017 3:20 PM >>>>> To: ntsysadm >>>>> Subject: [NTSysADM] Very strange problem file server - read vs. >>>>> write >>>>> >>>>> All, >>>>> >>>>> I have a 2012R2 file server running as a VM on vSphere 6.0. >>>>> >>>>> Here's what I'm seeing: >>>>> >>>>> Copy large file (win7 ISO) from file server to workstation, I get >>>>> roughly 12-13Mbytes/second, wired or wireless. >>>>> >>>>> Copy that file from workstation to server over a wireless >>>>> connection, same speed - 12-13Mbytes/second >>>>> >>>>> Copy that file from workstation to server over wired connection, >>>>> speed degrades to 1Mbyte/second or less >>>>> >>>>> Copy that file to another 2012R2 VM on the same host on the same >>>>> SAN volume (our print server), and speeds are 12-13Mbytes/second >>>>> for both wired and wireless. >>>>> >>>>> I've made sure that the following are disabled: RSS, atime, 8.3 >>>>> filename generation, TCP Chimney. >>>>> >>>>> RAM and CPU utilization on this machine are well within limits. >>>>> >>>>> I'm thoroughly stumped. >>>>> >>>>> Anyone have pointers for me? I'm about to raise a case with MSFT. >>>>> >>>>> Kurt >>>>> >>>>> >>>> >>>> >>> >> >> > >
