In-Memory Database Guide : Configuring the in‑memory database
  
Configuring the in‑memory database
You can configure solidDB® to create new tables as in-memory tables (M-tables) by default by setting the General.DefaultStoreIsMemory parameter to yes. Most other in-memory features are configured using the parameters in the [MME] section of the solid.ini file.
You need to pay special attention to controlling memory consumption; if the in-memory database or the server process uses up all of the available virtual memory in the system, you will be unable to add or update data. If the server uses up all of the physical memory and starts to use virtual memory, the server will continue to operate, but performance will be greatly reduced.
See also
Configuration parameters
Memory consumption