Parallelization support in AutoAttack [JATIC-I2-IBM]

[kieranfraser]

Description

Adding parallelization (CPU) support for AutoAttack to facilitate identification of attack combinations with lowest perturbations whilst maximizing CPU usage.

Addresses elements of #618, fixes #2256

Type of change

Please check all relevant options.

• Improvement (non-breaking)
• Bug fix (non-breaking)
• New feature (non-breaking)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Testing

Please describe the tests that you ran to verify your changes. Consider listing any relevant details of your test configuration.

• tests/attacks/evasion/test_auto_attack.py - added test_generate_parallel

Test Configuration:

• OS: macOS
• Python version: 3.10
• ART version or commit number: dev_1.16.0

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[codecov-commenter]

Codecov Report

Merging #2258 (b6595c9) into dev_1.16.0 (161c406) will increase coverage by 1.96%.
Report is 5 commits behind head on dev_1.16.0.
The diff coverage is 93.33%.

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@@              Coverage Diff               @@
##           dev_1.16.0    #2258      +/-   ##
==============================================
+ Coverage       83.87%   85.83%   +1.96%     
==============================================
  Files             318      318              
  Lines           28329    28356      +27     
  Branches         5157     5169      +12     
==============================================
+ Hits            23761    24340     +579     
+ Misses           3243     2708     -535     
+ Partials         1325     1308      -17     

Files Changed	Coverage Δ
art/metrics/metrics.py	89.93% <ø> (ø)
art/attacks/evasion/auto_attack.py	91.81% <91.30%> (+7.37%)	⬆️
art/attacks/attack.py	92.90% <100.00%> (+0.05%)	⬆️
art/defences/trainer/adversarial_trainer.py	92.30% <100.00%> (+0.27%)	⬆️
art/estimators/classification/pytorch.py	86.36% <100.00%> (+0.51%)	⬆️

... and 17 files with indirect coverage changes

[beat-buesser]

Hi @kieranfraser Thank you very much for adding the first multiprocessing feature to ART's attacks. I have added a few minor suggestions. Please let me know what you think!