CI: cache transformers in Azure (#1424)

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.azure/gpu-pipeline.yml

@@ -37,6 +37,7 @@ jobs:
 
  variables:
  DEVICES: $( python -c 'name = "$(Agent.Name)" ; gpus = name.split("_")[-1] if "_" in name else "0,1"; print(gpus)' )
+ HF_CACHE_DIR: "$(Pipeline.Workspace)/ci-cache_huggingface"
 
  container:
  image: "$(docker-image)"
@@ -95,6 +96,19 @@ jobs:
  python -c "import torch ; mgpu = torch.cuda.device_count() ; assert mgpu >= 2, f'GPU: {mgpu}'"
  displayName: 'Sanity check'
 
+ - task: Cache@2
+ inputs:
+ key: transformers | "$(Agent.OS)"
+ restoreKeys: mykey
+ path: $(HF_CACHE_DIR)
+ cacheHitVar: HF_CACHE_RESTORED
+ - bash: |
+ printf "cache location: $(HF_CACHE_DIR)\n"
+ printf "hit the HF cache: $(variables.HF_CACHE_RESTORED)\n"
+ mkdir -p $(HF_CACHE_DIR) # in case cache was void
+ ls -lh $(HF_CACHE_DIR) # show what was restored...
+ displayName: 'Show HF cache'
+
  - bash: python -m pytest torchmetrics --cov=torchmetrics --timeout=120 --durations=50
  workingDirectory: src
  displayName: 'DocTesting'
@@ -120,6 +134,8 @@ jobs:
  python -m codecov --token=$(CODECOV_TOKEN) --commit=$(Build.SourceVersion) --flags=gpu,unittest --name="GPU-coverage" --env=linux,azure
  ls -l
  workingDirectory: tests
+ env:
+ TRANSFORMERS_CACHE: $(HF_CACHE_DIR)
  displayName: 'Statistics'
 
  - task: PublishTestResults@2