Intel em NICs Suffering Performance Degradation on FreeBSD12
Reference FreeBSD bug report here:
Seems the issue is patched in newer kernel releases of FreeBSD.
Updated by Marcos Mendoza about 2 months ago
This is an issue with the following NICs:
em0@pci0:4:0:0: class=0x020000 card=0x125e8086 chip=0x105e8086 rev=0x06 hdr=0x00 vendor = 'Intel Corporation' device = '82571EB/82571GB Gigabit Ethernet Controller D0/D1 (copper applications)' class = network subclass = ethernet cap 01[c8] = powerspec 2 supports D0 D3 current D0 cap 05[d0] = MSI supports 1 message, 64 bit enabled with 1 message cap 10[e0] = PCI-Express 1 endpoint max data 128(256) RO NS max read 512 link x4(x4) speed 2.5(2.5) ASPM disabled(L0s/L1) ecap 0001 = AER 1 0 fatal 1 non-fatal 0 corrected
After switching the NIC to something that used the igb driver instead of the em iflib driver, the issue was fixed.
To add more details to this, the issue that was reported was ping spikes and timeouts over an OpenVPN connection after an upgrade to 2.5.2 from 2.4.5p1. IPsec and LAN were fine.