I'm using the function
rosbag can record lots of data from other ROS nodes. In a word, it will generate a huge file, such as a file of 200MB.
After generating such a file, I found that the buff/cache of the system increases a lot. Here is my capture:
You can see that after
buff/cache increased a lot, at the same time,
free decreased from 19983 to 10896.
I can't understand. As my understanding,
free means the free size of RAM,
buff/cache is the size of cache. Why can cache use the size of RAM? And I've also found that if I deleted the file generated by
buff/cache would get back from 17999 to 8925. Is this the action of the system? When will the
buff/cache increase? When will the