/data/retesteth/build/retesteth/retesteth -t DifficultyTests -- --all -j2 --nologcolor --exectimelog --clients t8ntool --testpath /data/tests 
Running tests using path: /data/tests
Running 7 test cases...
Retesteth config path: /home/ubuntu/.retesteth
Active client configurations: 't8ntool '
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfArrowGlacier": (1 of 7)
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Tests finished: 5
dfArrowGlacier time: 70.33, cputime: 2.77 (3%), t8ntime: 134.79 (191%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfByzantium": (2 of 7)
100%
Tests finished: 1
dfByzantium time: 83.63, cputime: 1.89 (2%), t8ntime: 82.07 (98%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfConstantinople": (3 of 7)
100%
Tests finished: 1
dfConstantinople time: 82.02, cputime: 1.84 (2%), t8ntime: 80.50 (98%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfEIP2384": (4 of 7)
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Tests finished: 3
dfEIP2384 time: 113.40, cputime: 4.41 (3%), t8ntime: 213.85 (188%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfFrontier": (5 of 7)
100%
Tests finished: 1
dfFrontier time: 82.84, cputime: 1.86 (2%), t8ntime: 81.30 (98%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfGrayGlacier": (6 of 7)
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Tests finished: 5
dfGrayGlacier time: 79.29, cputime: 2.60 (3%), t8ntime: 124.30 (156%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfHomestead": (7 of 7)
100%
Tests finished: 1
dfHomestead time: 82.08, cputime: 1.89 (2%), t8ntime: 80.51 (98%)

*** No errors detected
*** Total Tests Run: 17

*** Execution time stats
Total Time:                               : 593.59          :   17.26 (2%)              :  797.33 (134%)
dfEIP2384                             time: 113.40   cputime:    4.41 (3%)       t8ntime:  213.85 (188%)
dfByzantium                           time: 83.63    cputime:    1.89 (2%)       t8ntime:   82.07 (98%)
dfFrontier                            time: 82.84    cputime:    1.86 (2%)       t8ntime:   81.30 (98%)
dfHomestead                           time: 82.08    cputime:    1.89 (2%)       t8ntime:   80.51 (98%)
dfConstantinople                      time: 82.02    cputime:    1.84 (2%)       t8ntime:   80.50 (98%)
dfGrayGlacier                         time: 79.29    cputime:    2.60 (3%)       t8ntime:  124.30 (156%)
dfArrowGlacier                        time: 70.33    cputime:    2.77 (3%)       t8ntime:  134.79 (191%)