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arXiv · 2112.10106

New Mechanism for Fast System Calls

Till Miemietz·Maksym Planeta·Viktor Laurin Reusch
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Abstract

System calls have no place on the fast path of microsecond-scale systems. However, kernel bypass prevents the OS from controlling and supervising access to the hardware. In this paper we introduce the fastcall space, a new layer in the traditional OS architecture, that hosts fastcalls. A fastcall implements the fast path of a traditional kernel operation and can stay on the fast path, because the transition to the fastcall space is $\approx\times 15$ faster than to the kernel space. This way the OS does not give up the control over device access, whereas the applications maintain their performance.

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Till Miemietz, Maksym Planeta, Viktor Laurin Reusch. 2021-12-19. New Mechanism for Fast System Calls. https://arxiv.org/abs/2112.10106

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