42 lines
1.5 KiB
Plaintext
42 lines
1.5 KiB
Plaintext
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Rosetta Operating System: Protocols
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===================================
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1 Introduction
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--------------
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Due to its nature as a message-passing operating system, a standard
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"langauge" is needed in order to allow different components of the system
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to communicate with each other. This document describes the communication
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layer built on top of kernel IPC primitives to facilitate the fast transfer
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of structured data between components.
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2 Design Goals
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--------------
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The key consideration for Protocols is low-overhead and speed. All system
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functionality is accessed via sending messages, so any speed or memory costs
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incurred will affect the performance of the entire system.
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In addition, Protocols should be language-agnostic. Two components written
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in two different programming languages should be able to communicate as long
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as they both understand the same protocol.
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3 Overview
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----------
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Protocols is a very thin layer overtop of Mango ports. It provides a
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declarative language for describing message layouts in a language-agnostic
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format, and a tool for generating concrete implementations of protocols in
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various programming languages.
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Protocols makes heavy use of Mango's I/O vectors facility to avoid performing
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any dynamic memory allocation or unnecessary copying of data. As often as
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possible, any parameters you pass to a protocol function will be copied
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directly into the address space of the recipient. This makes Protocols
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essentially free to use.
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