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3897 :: [Quick tip] Store your "nimcache" folders in temp directory.

• Tiberium (orginal) [2018-06-07T22:14:19+02:00] view original

  I took the config from this comment by zah, but changed it a bit ("not release" instead of "debug").

  You can place this into <nim folder>/config/nim.cfg or into ` ~/.config/nim.cfg`:

  @if unix:
    @if not release:
      nimcache = "/tmp/nimcache/d/$projectName"
    @else:
      nimcache = "/tmp/nimcache/r/$projectName"
    @end
  @end
  
  @if windows:
    @if not release:
      nimcache = r"C:\Temp\nimcache\d\$projectName"
    @else:
      nimcache = r"C:\Temp\nimcache\r\$projectName"
    @end
  @end
  Run

  You can change the directories to your liking if you want to.

  This is mostly useful for big projects with a lot of files, but it may also have some impact on small ones.

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• mratsim (orginal) [2018-06-08T12:46:31+02:00] view original

  You need to mount /tmp as a tmpfs or ramdisk too for that to make a difference: see tutorial here https://wiki.archlinux.org/index.php/tmpfs

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• federico3 (orginal) [2018-06-08T13:22:11+02:00] view original

  Unless there are unnecessary sync() being done, and excluding cache warm-up, there should be no difference between using tmpfs or not.

  A quick benchmark with an 80 seconds long compilation on ext4 vs ext4 under eatmydata vs tmpfs shows no difference.

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• Tiberium (orginal) [2018-06-08T13:59:55+02:00] view original

  "Under systemd, /tmp is automatically mounted as a tmpfs even though no entry is specified in /etc/fstab."

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• Stefan_Salewski (orginal) [2018-06-08T18:36:09+02:00] view original

  Of course difference is not speed, as SSD's are really fast. Difference is, that too many write Ops may damage SSD. So I am using /tmp for nimcache since I bought my last SSD, two years ago. And I recommended using /tmp a few times already in Forum.

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• federico3 (orginal) [2018-06-09T20:03:53+02:00] view original

  This has little to do with SSD speed and wear, as the virtual memory caches reads and writes as aggressively as required, unless the system is under very high memory pressure and in that case using tmpfs only exacerbates the problem.

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• dom96 (orginal) [2018-06-09T20:09:40+02:00] view original

  AFAIK write wear isn't much of a concern with modern SSDs nowadays. Would love to be proven wrong though.

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• stbalbach (orginal) [2018-06-19T05:05:43+02:00] view original

  I have a ramdisk largely unused and now compile is speedier. Thanks for the suggestion.

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