[erlang-questions] Mnesia table replication scheme
Tue Mar 1 18:46:23 CET 2016
I'm storing user accounts and organizations (a tree of users, i.e.
departments, sub-departments, etc) in mnesia tables. Modification to
the data is not very frequent, i.e. not as frequent as a message queue.
I can't afford losing the data. Assume I have 9 erlang nodes (Linux VMs
in a clound), and I haven't decided how many of them should be used for
handling client connections and how many should be used for data
I know that the more nodes a table is replicated on, the slower writing
to it will be; I also know that ram copies are faster than disk copies;
I am seeking to find a balance between performance and data safety. How
should the tables be replicated? Should I use ram copies or disk copies
or a hybrid scheme? Can the data be in ram copies on some nodes and
backed up in disk only copies on some other nodes? If this is possible,
will it provide performance as ram copies while still have data safety
like disk copies?
What is the best practice here?
More information about the erlang-questions