Kernel output:
[   94.361312] sched: RT throttling activated

top output:
 PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
 145 root     -51   0       0      0      0 R  95.5   0.0   1:11.22 oa-tc6-spi-thread

link stats:
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
    link/ether 32:c2:7e:22:93:99 brd ff:ff:ff:ff:ff:ff
    RX:  bytes packets errors dropped  missed   mcast
       3371902    7186      0      48       0       0
    RX errors:  length    crc   frame    fifo overrun
                     0      0       0       0       0
    TX:  bytes packets errors dropped carrier collsns
      10341438    8071      0       0       0       0
    TX errors: aborted   fifo  window heartbt transns
                     0      0       0       0       1
state:
Completly borked, can't ping in or out, bringing the interface down then up
has no effect.

Completely borked is not good. 

I'd be keen on hearing what Microchips plans to address. If tracking
down performance issues is a priority I'll probably not spend any time
on it, if not then I'll definetly dig into it more.

Borked ! = performance issue. This should be addressed. Lets see if
the python scripts are enough to be able to reproduce it.

We should not rule out differences in SPI drivers. So it might be you
need to debug this, if Microchip cannot reproduce it.

I would also suggest you enable the "kernel hacking" debug features
for finding deadlocks, bad spinlocks, stuck RT tasks etc. That might
give some clues.

	Andrew