I would like to deactivate the disk cache for /dev/mmcblk0p1 in order to preserve more RAM for other system parts while playing 2160p video off /dev/mmcblk0p1.
2160p videos ravenously wipe the RAM cache from other programs. After watching 2160p video, other programs need to access files from the original disk again because the 2160p video footage occupied the RAM cache.
How can I exclude /dev/mmcblk0p1 selectively from the disk cache?
Related question: How to exclude programs from writing to RAM block cache? (e.g. media player).