# systemd-tmpfiles: raise the USB filesystem buffer for large camera frames.
#
# WHY: known-issues #19. usbcore.usbfs_memory_mb defaults to 16 MB, far below a
# single full-resolution frame, and reverts on every reboot. 1000 is the value
# the Allied Vision documentation asks for.
#
# 'w' writes the value if the file exists and never creates it, so this is inert
# on a machine without usbcore. Applied at boot by systemd-tmpfiles-setup.
# The kernel-cmdline alternative (usbcore.usbfs_memory_mb=1000 in GRUB) does the
# same job earlier; this one is chosen because it needs no bootloader edit and is
# undone by deleting one file.
w /sys/module/usbcore/parameters/usbfs_memory_mb - - - - 1000