Roland McGrath
27 linhas
1.2 KiB
Markdown
27 linhas
1.2 KiB
Markdown
# Magenta and LK
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LK is a Kernel designed for small systems typically used in embedded
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applications. It is a good alternative to commercial offerings like
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[FreeRTOS](http://www.freertos.org/) or [ThreadX](http://rtos.com/products/threadx/).
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Such systems often have a very limited amount of ram, a fixed set of peripherals
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and a bounded set of tasks.
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On the other hand, Magenta targets modern phones and modern personal computers
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with fast processors, non-trivial amounts of ram with arbitrary peripherals
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doing open ended computation.
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Magenta inner constructs are based on [LK](https://github.com/littlekernel/lk) but
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the layers above are new. For example, Magenta has the concept of a process but LK
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does not. However, a Magenta process is made of by LK-level constructs such as
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threads and memory.
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More specifically, some the visible differences are:
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+ Magenta has first class user-mode support. LK does not.
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+ Magenta is an object-handle system. LK does not have either concept.
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+ Magenta has a capability-based security model. In LK all code is trusted.
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Over time, even the low level constructs will change to accomodate the new
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requirements and to be a better fit with the rest of the system.
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