Copy-on-write is a resource-management technique where duplicated items will not be allocated new resources until there is a modification request. This means that copy and original process will share the same resources for the item.
Copy-on-write
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Mach’s Networking
To improve the efficiency, Mach caches the remote memory objects into local memory. For local memory objects, it passes the messages by merely moving the pointer to point to the shared memory objects. For all messages, if they are local to the machine, especially if they are large too, they are 202203251058. Otherwise, they will be handled by 202204231514#.
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Linux Memory Management
The resource management for newly recreated child process by
forksystem call will be done in #202203251058. They will point to the same process structure that their parent is using. This is crucial for I/O instructions since copying the file contents into the child’s memory space can be costly. If the child wants to modify the process structure, #202204081225 will then copy the process structure and other necessary system resources for it to prevent #202112061109. -
Docker Container
Upon running, #202110201636 will create a layer on top of image layer (describe in #202110201654). The changes of file which located in image layer will be done in #202203251058 where all the changes will happen in container layer.