what are pagecache, dentries, inodes?
问题 Just learned these 3 new techniques from https://unix.stackexchange.com/questions/87908/how-do-you-empty-the-buffers-and-cache-on-a-linux-system: To free pagecache: # echo 1 > /proc/sys/vm/drop_caches To free dentries and inodes: # echo 2 > /proc/sys/vm/drop_caches To free pagecache, dentries and inodes: # echo 3 > /proc/sys/vm/drop_caches I am trying to understand what exactly are pagecache, dentries and inodes. What exactly are they? Do freeing them up also remove the useful memcached and