/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: 64.55, cputime: 2.60 (4%), t8ntime: 123.54 (191%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfByzantium": (2 of 7)
100%
Tests finished: 1
dfByzantium time: 73.42, cputime: 1.69 (2%), t8ntime: 72.02 (98%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfConstantinople": (3 of 7)
100%
Tests finished: 1
dfConstantinople time: 74.63, cputime: 1.71 (2%), t8ntime: 73.21 (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: 102.95, cputime: 4.17 (4%), t8ntime: 193.84 (188%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfFrontier": (5 of 7)
100%
Tests finished: 1
dfFrontier time: 74.26, cputime: 1.73 (2%), t8ntime: 72.82 (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: 71.03, cputime: 2.45 (3%), t8ntime: 111.84 (157%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfHomestead": (7 of 7)
100%
Tests finished: 1
dfHomestead time: 74.61, cputime: 1.74 (2%), t8ntime: 73.16 (98%)

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

*** Execution time stats
Total Time:                               : 535.45          :   16.09 (3%)              :  720.43 (134%)
dfEIP2384                             time: 102.95   cputime:    4.17 (4%)       t8ntime:  193.84 (188%)
dfConstantinople                      time: 74.63    cputime:    1.71 (2%)       t8ntime:   73.21 (98%)
dfHomestead                           time: 74.61    cputime:    1.74 (2%)       t8ntime:   73.16 (98%)
dfFrontier                            time: 74.26    cputime:    1.73 (2%)       t8ntime:   72.82 (98%)
dfByzantium                           time: 73.42    cputime:    1.69 (2%)       t8ntime:   72.02 (98%)
dfGrayGlacier                         time: 71.03    cputime:    2.45 (3%)       t8ntime:  111.84 (157%)
dfArrowGlacier                        time: 64.55    cputime:    2.60 (4%)       t8ntime:  123.54 (191%)