1. A computer implemented method of creating a backup of data in an In-memory database system, the method comprising receiving a request to create a backup of a data set from a main memory of the system, disabling manipulation of the data set by the system, invoking a data structure comprising meta-data information identifying one or more data blocks in the main memory that form the data set, creating a snapshot of the data structure, storing the snapshot of the data structure in the mam memory, enabling manipulation of the data set by the system, receiving a request from the system to modify at least one block of the one or more blocks of data, copying the at least one data block to a free memory block in the main memory to perform the requested modification on the copied data block, and updating the data structure by replacing original meta-data identifying the at least one block of data with new meta-data identifying the free memory block, and creating the backup of the data set by duplicating the data set using meta-data information from the snapshot of the data structure and storing the duplicated data set in a target memory.