Originally posted by oiaohm
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But, often times, you have to do IPC instead of a function call. This is true even on a Linux system, which does run the kernel in supervisor mode so it won't need to use the IPC itself, but still runs everything else in user mode processes, and these will need to talk to each other.
Multi-server systems will, by design, need to do a lot of IPC, relative to non-multiserver systems. The effect this has in performance is a function of the increase in IPC and the cost of IPC.
Yes sel4 claim about being the fastest Microkernel that is also disproved in that 2020 paper I have referenced.
Notice that seL4 is a formally proven microkernel, whereas ChCore/UnderBridge is but a paper and PoC.
I can be faster than seL4 too, it doesn't actually take much effort to make a PoC with a constrained scenario. However, designing a kernel that is fast in general and practical for the industry to use is not trivial.
The Microkernel world is very guilty of attempt to sweep their issues under the rug and hope nobody notices. Sorry a party like me notices.
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The reality Linus 1992 statement on Microkernel IPC being horrible slow is still just as true today.
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Yes it not well hidden when you know what you are looking at.
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The reality Linus 1992 statement on Microkernel IPC being horrible slow is still just as true today.
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Yes it not well hidden when you know what you are looking at.
https://www.cosy.sbg.ac.at/~clausen/...-rebuttal.html
Totally not true. What you just describe is what the real time patch set to the Linux kernel provided and has been progressive merged.
Linux doesn't have any fast paths with guaranteed maximum latency. Everything is Best Effort..
ayumu; like it or not you are writing a huge stack of stuff not based in fact.
But you you think that the Linux kernel and other monolithic kernels has not improved IPC over the years? This is the catch Linux kernel IPC cost has decreased faster than the Microkernel IPC cost.
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