[xcpu] not sure where the failure is but:

[ron minnich]

<<< (0x1bd4180) Tread tag 0 fid 2 offset 0 count 4294967272
>>> (0x1bd4180) unknown type 0
*** glibc detected *** /usr/local/sbin/xcpufs: free(): invalid next
size (normal): 0x0000000001be07b0 ***
Note the Tread

ron