Global architecture |
Some definitions
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RAM as a cache
The videotape metaphor
The kernel loads components in memory. When a component (or piece of information) is not used anymore, or because memory is required to load another component (or piece of information), the kernel writes the unused component on disk, AFTER any content, in a sequential order, just like a tape. If you look back to load some older components (or pieces of information), you could load what's around it too, since chances are that they are used in the same context of operation. But the kernel will not wait until you ask for them to get loaded... they will get loaded at once. |
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Messaging
Each process has a message receive queue, which is registered with the messaging engine. A message can be sent to an integer value reference or named reference. The messaging engine checks if the integer value reference is a real pid or is the named reference is registered as a receiver. It then forwards the message to the appropriate receiver. A message is always passed with its own structure, being generated by the programmer or by the interpreter/compiler. This structure can be used to validate a message structure against the receiver waited-for structure. Data types
A string is an array of integers. Integers are of variable size.
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