On Thu, Oct 10, 2019 at 09:52:52AM +0200, Vieri Di Paola wrote: > I previously posted about a problem I was seeing when using TEE in a > heavy-duty Shorewall router. If anyone ever comes up with a sluggish > network with ping loss and the likes, check your FW's processes and > look for ksoftirqd. You should see one for every CPU core. If CPU > usage per process is high, and if you also experience sporadic ping > loss to the FW then check /proc/interrupts. > Search for the eth*/enp* device/s with the highest interrupts. > Then check the card info with lspci -vv. Look for MSI and MSI-X. If > you see "Enable-" then enable CONFIG_PCI_MSI in your kernel source and > rebuild it. > If you don't see MSI or MSI-X then buy a new NIC. > If you have a lot of packets going through the router then get a NIC > with MSI-X support. > > Change your busiest NIC, reboot the kernel and your lspci should show > you something like this: > > Capabilities: [70] MSI-X: Enable+ Count=10 Masked- > > I don't know what "Count" means here, but I guess that the higher, the better.
Count is the size of the MSI-X Table, which is how many interrupt vectors it supports. So if it supports a lot, it means it can have multiple receive queues doing RSS with a unique interrupt for each queue, each going to a different CPU. Certainly helps handle a lot more traffic. Looking at a couple of NICs here, I see 129 on an intel X722, and 64 on a Mellanox ConnectX-4 (although I think that can go higher if virtualization support is disabled). -- Len Sorensen _______________________________________________ Shorewall-users mailing list Shorewall-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/shorewall-users
