message: avoid overloading the CI system
  This adds the -l parameter to ninja, which limits it to single-core
  execution unless the load-average is below the number of cores.
diff: @@ -58,7 +58,7 @@ stages:
  -DGINKGO_BUILD_OMP=${BUILD_OMP} -DGINKGO_BUILD_CUDA=${BUILD_CUDA}
  -DGINKGO_BUILD_HIP=${BUILD_HIP}
  -DGINKGO_BUILD_TESTS=ON -DGINKGO_BUILD_EXAMPLES=ON
  - - ninja -j${NUM_CORES}
  + - ninja -j${NUM_CORES} -l `nproc`
  dependencies: []
  except:
  - schedules
  @@ -83,7 +83,7 @@ stages:
  -DGINKGO_BUILD_OMP=${BUILD_OMP} -DGINKGO_BUILD_CUDA=${BUILD_CUDA}
  -DGINKGO_BUILD_HIP=${BUILD_HIP}
  -DGINKGO_BUILD_TESTS=ON -DGINKGO_BUILD_EXAMPLES=ON
  - - ninja -j${NUM_CORES} install
  + - ninja -j${NUM_CORES} -l `nproc` install
  - |
  (( $(ctest -N | tail -1 | sed 's/Total Tests: //') != 0 )) || exit 1
  - ctest -V
  