What do columns for TM memory usage in Flink UI Console mean?

[John Tipper]

Hi all,

I can't find mention of what the columns mean for the "Outside JVM Memory' for 
the Task Manager in the Flink console.

I have:


                  Count             Used        Capacity
Direct            4,203       227 MB      227MB
Mapped            0           0 B               0 B

What is the unit of measure for "Count"?