MemToLeave area! How to monitor?

Gurus,
Occasionally I get the error of "WARNING:  Failed to reserve contiguous
memory of Size= 65536."
What is the unit for this size, is it bytes or KB?  Additionally,

I have set up 511 MB for MemToLeave area by adding -g384 for Sql2k SP3a on
AWE enabled system. I have total of 16 GB of RAM, of which 14 GB is set up
maximum for Sql server.
If I look at Perfmon counter of Process->Private bytes for sql server
process it gives me 224 MB.
If I look at sqlserver.exe process on task manager it gives me 215MB.
If I look at DBCC memorystatus, OS in use, it gives me 12 MB.

I would like to know, How can I calculate exactly how much memory is being
assigned and how much in use from MemToLeave area by looking at above
mentioned counters or any other perfmon or dbcc counters?

I really appreciate any input on this matter.