Hello!
For about three months now I have rented a "EX40" server at the German hoster Hetzner (hardware specs see link below) which has a Realtek onboard NIC.
Hetzner Online AG: Dedicated Root Server EX40
I'm using this server since may with ESXi 5.0.0 (for reasons of "never change a running system unless required", I know it's a bit dated, but since it's still supported and patched...)
A few weeks ago, and last time yesterday, I found the following error messages in vmkernel.log, which I was probably roughly able to relate to traffic peaks (sudden increase in transmitted/received packets when doing fast downloads or bandwidth tests):
The physical NIC is frozen then for about 5 seconds and the log shows:
2014-08-03T10:02:45.761Z cpu6:3659)WARNING: NetSched: 1857: Scheduler [0x410005193180] lock up [stopped=0] for vmnic0:
2014-08-03T10:02:45.761Z cpu6:3659)WARNING: NetSched: 1868: detected at 2508692839 while last xmit at 2508687164 and 14/20440 packets/bytes in flight [window full 1] and binary heap size 1 last queue at 2508692683 [stress 0]
2014-08-03T10:02:45.761Z cpu6:3659)WARNING: NetSched: 1877: Packets completion seem stuck, issuing reset on vmnic0 [stress 0]
It does not always happen at high transfer rates. I've been doing transfers and tests for hours already without this effect occurring, and then out of the blue it happens sporadically.
Further info: I'm running a virtual machine with "pfSense" as router/firewall, which uses virtual e1000 NICs (VMXNET does not work properly on pfSense). Other VMs have Windows Server 2k3/2k8 and Ubuntu 10.04/12.04.
I already found a patch regarding a similar issue in the ESXi downloads section, but that doesn't seem to apply to me. For one, I have the latest 5.0.0 patch level, and also I'm not using an e1000 physical NIC but a Realtek one.
Any ideas about this? Any system settings that one could tweak to prevent this?
I could have my hoster put an Intel NIC into my server which is all okay if that should help. Or should I upgrade to 5.1.0 or 5.5.0? If possible I'd like to avoid that, since, well, "never change..." and so on. 
Thanks a lot in advance for hints!
