4 ms·

umount will block until the writes are finished, though

• scarygliders 3y ago
  Indeed it will but I just like to make /sure/ ;)
• megous 3y ago
  Not always.
  • TeMPOraL 3y ago
    Not always, as in it'll terminate earlier, or as in it'll continue blocking indefinitely after the writes are finished? Because I think I've experienced the second case a few times.
    • megous 3y ago
      Not always as depending on flags you pass to the umount2 syscall.
• asveikau 3y ago
  I almost always run sync after unmount on USB sticks or SD cards. Old habits and superstitions, I guess. Recently I saw a USB stick's activity LED stay on long after unmount. I'm not sure if it was writing or something else.
  • kzrdude 3y ago
    Triple sync is at the end of my backup-to-usb disk script
  • lelanthran 3y ago
    Possible. The little microcontroller that does the actual write to pages of flash might actually be busy moving things around and doing other housekeeping after the disk is unmounted but while it still has power. I wrote the firmware for a flash based system, and used powered-yet-unmounted time to save a few statis to the uC's internal flash.
  • bayindirh 3y ago
    I have seen that too. It generally means the drive is doing write leveling and/or other tasks. If I have time, I wait for that, too. However, LEDs become rarer and rarer these days.