Are memory only databases shared?

Question

Greetings,
If I open several db files and create a memory db in the same environment, and do this from several concurrently running processes, it is possible that the memory db would be shared? I need the memory db to be private to each process and wondered how I can ensure that it is?
The only difference in the way I am opening the db files vs. the memory db is by passing null for a filename and DB_CREATE for the memory db.
Thanks,
Matthew

Answer 1

Thanks for the reply. I am opening each memory database with its own handle (didn't know it was possible to do otherwise?)
If multiple private databases are opened in the same shared environment, they
will each occupy space in the cache, so you need to ensure that the cache is
large enough to hold all of the data if you want to make sure that the data stays
in memory.What happens when I open the environment from multiple processes, and each process is calculating the cache size based on the lookup files it will need? Your statement made me think that maybe I could be causing a problem for myself. I have about 20 or so lookup tables, but each process only uses a subset of those based on its job.
So if process #1 opens 10 of the lookup tables and requests a cache large enough to keep all the lookups in memory, what happens when process #2, #3, #4, etc. start and request a cache size for their respective lookups? All processes open the same database files in the same directory, so are they also sharing the same environment?
Matthew