A. Compile the list of data files to be backed up based on the rules of the backup algorithm.
B. Based on the number of channels and the number of data files backed up at the same time, create a memory buffer (input/output) from the Oracle shared memory segment, usually in the PGA, but sometimes the SGA is also recommended. The channel service process begins to read the data file, first filling the input buffer.
C. After the input is full, write the data of the input buffer to the output buffer through the memery to memery write method, and detect whether the data is damaged.
D. After the output buffer is full, the data file will be pushed to the backup location.
E. Once all the files are filtered through the memory buffer, the backup piece will be completed, and the backup piece completion time and name will be written in the target database control file.
