All except setup in ubuntu_performance_fio fails on spinning disks

Appears to be a new test suite on bionic, so would not consider to be a regression.

Failing on Michael

List of tests failed:

ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-0-wr-100-rand-blk-128k-jobs-16
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-0-wr-100-rand-blk-8k-jobs-64
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-0-wr-100-seq-blk-128k-jobs-16
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-0-wr-100-seq-blk-8k-jobs-64
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-100-wr-0-rand-blk-128k-jobs-16
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-100-wr-0-rand-blk-8k-jobs-64
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-100-wr-0-seq-blk-128k-jobs-16
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-100-wr-0-seq-blk-8k-jobs-64
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-75-wr-25-rand-blk-128k-jobs-16
ubuntu-performance-fio-michael-sdb-mb1000gdunu-zfs-rd-75-wr-25-rand-blk-8k-jobs-64

All except the first test have similar output of "Device or resource busy: '/mnt/autotest-fio'". Seems to get caught up on the first test.:

02/05 03:34:51 DEBUG| utils:0116| Running 'sync'
02/05 03:34:51 DEBUG| utils:0116| Running 'getconf PAGE_SIZE'
02/05 03:34:51 DEBUG| utils:0153| [stdout] 4096
02/05 03:34:51 DEBUG| utils:0116| Running 'getconf _AVPHYS_PAGES'
02/05 03:34:51 DEBUG| utils:0153| [stdout] 7682344
02/05 03:34:51 INFO |ubuntu_per:0369| Test 1 of 3:
02/05 03:34:51 INFO |ubuntu_per:0130| Testing on device /dev/sdb with file system zfs
02/05 03:34:51 INFO |ubuntu_per:0130|
02/05 03:34:51 ERROR| test:0414| Exception escaping from test:
Traceback (most recent call last):
  File "/home/ubuntu/autotest/client/shared/test.py", line 411, in _exec
    _call_test_function(self.execute, *p_args, **p_dargs)
  File "/home/ubuntu/autotest/client/shared/test.py", line 830, in _call_test_function
    raise error.UnhandledTestFail(e)
UnhandledTestFail: Unhandled OSError: [Errno 16] Device or resource busy: '/mnt/autotest-fio'
Traceback (most recent call last):
  File "/home/ubuntu/autotest/client/shared/test.py", line 823, in _call_test_function
    return func(*args, **dargs)
  File "/home/ubuntu/autotest/client/shared/test.py", line 291, in execute
    postprocess_profiled_run, args, dargs)
  File "/home/ubuntu/autotest/client/shared/test.py", line 212, in _call_run_once
    self.run_once(*args, **dargs)
  File "/home/ubuntu/autotest/client/tests/ubuntu_performance_fio/ubuntu_performance_fio.py", line 433, in run_once
    self.run_fio_tests(test_name, media, ramdisk_bytes)
  File "/home/ubuntu/autotest/client/tests/ubuntu_performance_fio/ubuntu_performance_fio.py", line 370, in run_fio_tests
    values[i] = self.run_fio(testname, ramdisk_bytes, media)
  File "/home/ubuntu/autotest/client/tests/ubuntu_performance_fio/ubuntu_performance_fio.py", line 272, in run_fio
    self.setup_drive()
  File "/home/ubuntu/autotest/client/tests/ubuntu_performance_fio/ubuntu_performance_fio.py", line 133, in setup_drive
    os.rmdir(TEST_MNT)
OSError: [Errno 16] Device or resource busy: '/mnt/autotest-fio'