get-nprocessors.sh 2.2 KB

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  1. #!/usr/bin/env bash
  2. # Copyright 2017 Google Inc.
  3. # All Rights Reserved.
  4. #
  5. #
  6. # Redistribution and use in source and binary forms, with or without
  7. # modification, are permitted provided that the following conditions are
  8. # met:
  9. #
  10. # * Redistributions of source code must retain the above copyright
  11. # notice, this list of conditions and the following disclaimer.
  12. # * Redistributions in binary form must reproduce the above
  13. # copyright notice, this list of conditions and the following disclaimer
  14. # in the documentation and/or other materials provided with the
  15. # distribution.
  16. # * Neither the name of Google Inc. nor the names of its
  17. # contributors may be used to endorse or promote products derived from
  18. # this software without specific prior written permission.
  19. #
  20. # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21. # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22. # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23. # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  24. # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  25. # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  26. # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27. # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28. # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29. # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  30. # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31. # This file is typically sourced by another script.
  32. # if possible, ask for the precise number of processors,
  33. # otherwise take 2 processors as reasonable default; see
  34. # https://docs.travis-ci.com/user/speeding-up-the-build/#Makefile-optimization
  35. if [ -x /usr/bin/getconf ]; then
  36. NPROCESSORS=$(/usr/bin/getconf _NPROCESSORS_ONLN)
  37. else
  38. NPROCESSORS=2
  39. fi
  40. # as of 2017-09-04 Travis CI reports 32 processors, but GCC build
  41. # crashes if parallelized too much (maybe memory consumption problem),
  42. # so limit to 4 processors for the time being.
  43. if [ $NPROCESSORS -gt 4 ] ; then
  44. echo "$0:Note: Limiting processors to use by make from $NPROCESSORS to 4."
  45. NPROCESSORS=4
  46. fi