[LU-10217] Sanity 248 fails with newer dd output

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.11.0, Lustre 2.10.3
• Affects Version/s: Upstream, Lustre 2.10.1, Lustre 2.11.0
• Environment: SlE12SP2/SP3
• Severity: 3
• Assignee: Bob Glossman (Inactive)
• Reporter: Nikolay Borisov (Inactive)

Description

Running the sanity test suite on SLES12SP2/SP3 fails with the following error:

Test 1: verify that fast read is 4 times faster on cache read
(standard_in) 1: illegal character: M
(standard_in) 1: syntax error
(standard_in) 1: illegal character: M
./sanity.sh: line 14321: [: -eq: unary operator expected
 sanity test_248: @@@@@@ FAIL: fast read was not 4 times faster:  MiB) vs MiB) 
  Trace dump:
  = /usr/lib64/lustre/tests/test-framework.sh:5293:error()
  = /usr/lib64/lustre/tests/test-framework.sh:5326:error_not_in_vm()
  = ./sanity.sh:14322:test_248()
  = /usr/lib64/lustre/tests/test-framework.sh:5569:run_one()
  = /usr/lib64/lustre/tests/test-framework.sh:5608:run_one_logged()
  = /usr/lib64/lustre/tests/test-framework.sh:5407:run_test()
  = ./sanity.sh:14345:main()

This is due to changed output dd has in recent versions:

32768+0 records in
32768+0 records out
134217728 bytes (134 MB, 128 MiB) copied, 3,85718 s, 34,8 MB/s

Essentially there are more fields being added with the inclusion of base 2 value. Further testing showed that sometimes dd can print the quantity of elapsed time in scientific notation, which is not understood by bc:

4096 bytes (4,1 kB, 4,0 KiB) copied, 9,1229e-05 s, 44,9 MB/s