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SubjectRe: Some very thought-provoking ideas about OS architecture.
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> This is partly right, and partly wrong. Actually, some light-weight
> message passing protocols can be cheaper than function calls. A function

No. A message pass is a function call is a message pass.

> call to a kernel function requires two state transitions (user->kernel
> and back), and two context switches; since the kernel wants to massage
> different data than the user process, it also has an effect on the
> cache.

No context switches, just a pair of priviledge transitions.

> Message passing can make this cheaper, if (and only if) your messages
> are handled asynchronously. Put a bunch of messages into your shared
> memory message buffer (simple *ptr++ = id; *ptr++ = arg; ...), and when
> you are done, do the one state transition and context switch, and let

function(int num_jobs, struct job *joblist)

next ?



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