Messages in this thread | | | Date | Mon, 14 Apr 2008 17:41:29 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH] Replace completions with semaphores |
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* Matthew Wilcox <matthew@wil.cx> wrote:
> On Sun, Apr 13, 2008 at 09:05:13AM +0200, Ingo Molnar wrote: > > there's also another aspect: completions are faster a bit > > in theory, because they know that they will schedule most of the time - > > while semaphores assume that they will _not_ schedule. (And that's > > exactly because the intent of the developer when using a completion is > > crystal clear.) > > In practice though, the current implementation is slower. [...]
any URL to benchmarks?
> [...] Of course, that's fixable, and I strongly suspect that the > current users of completions simply don't care about speed -- the > normal use of completions is in startup and shutdown paths where a > millisecond extra isn't going to be noticable.
completions and semaphores act in the sub-microsecond range, not in the milliseconds range.
Ingo
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