What is the purpose of the tag field in a lock state structure?

[John Wilson]

Hi,

I'm not clear with what the 2 byte TAG field in the lock state structure is
used for. Please explain.

https://github.com/apache/ignite/blob/master/modules/core/src/main/java/org/apache/ignite/internal/util/OffheapReadWriteLock.java#L26

Thanks,
John