I'm running debian Jesse on a broadwell D-1527 with two embedded x552 10Gbe ports. When I try to enable 63 VFs on each x552 I hit a limit of 55 VFs before get "ixgbevf 0000:02:1f.4: Unable to allocate MSI-X interrupts" errors. It seems the 55 VFs is a total limit, meaning the total numbers of VFs between the two x552s cannot exceed 55VFs.
I then tried reducing MSI_X_VF_N from the default value of 0x2 to 0x1. This resulted in increasing the max to 86 VFs before I got the "Unable to allocate MSI-X interrupts" errors.
What might be the limiting the maximum MSI_X allocations?
Additional information: Enabling X2APIC seems to have increased the number of VFs I can instantiate to 106. If I reduce MSI_X_VF_N to 1 I can get all 126. I'd still like to find out how to get to 126 VFs with the default MSI_X_VF_N setting of 2.
Thank you for joining the Processor community.
Regarding your inquiry, the best place to get more answers is our Embedded community; https://embedded.communities.intel.com/ Forum: Embedded Community |Embedded Community. They might be able to provide more feedback regarding this matter. As a suggestion, I would also recommend using the Debian Forums; http://forums.debian.net/ Debian User Forums • Index page.