By default, OnixS .NET Framework FIX Engine stores all incoming and outgoing messages, session state data, as well as the Engines primary log in files in the MsgStorage subfolder of the folder, in which the OnixS .NET Framework FIX Engine assembly resides.

However, it is possible to store all session-related logging data in memory. For these purposes, the storageType parameter of the Session(String, String, ProtocolVersion, Boolean, SessionStorageType) constructor is available. Once the MemoryBasedStorage value will be specified as the value for the storageType parameter, session-related data will be logged into memory.

Also, you can use the asynchronous File-Based Session Storage which combines the good-performance with the File-Based Session Storage functionality, in this case, the AsyncFileBasedStorage value should be specified as the value for the storageType parameter.

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