Solve the problem of excessive buff/cache memory usage

1. After the Linux server has been used for a long time, the buff/cache memory will be excessively occupied.

As shown in the figure:

2. You can use the following command to clear the cache memory

echo 1 > /proc/sys/vm/drop_caches
echo 2 > /proc/sys/vm/drop_caches
echo 3 > /proc/sys/vm/drop_caches

3. Check again after clearing, the effect is remarkable