Introduction - If you have any usage issues, please Google them yourself
For the same process, many loaded, will create more than one instance of its first instance A process address space (4GB), the second instance of B, the process address space (4GB), the address of each process instance space has multiple code pages and multiple data page A is loaded for the first time, they will be mapped into the virtual memory, when out of the data page is modified, the system will first intercepted, then application A attempts to write memory page allocation into a new memory, and then copy the content of the page, the last application to write to the newly allocated memory block. Application A data page has pointed to the new place where the main use of the page write when replication features.