Messages in this thread | | | Date | Fri, 29 Aug 2008 09:12:29 -0700 | From | Arjan van de Ven <> | Subject | Re: [patch 0/5] Nano/Microsecond resolution for select() and poll() |
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On Fri, 29 Aug 2008 17:54:27 +0200 Arnd Bergmann <arnd@arndb.de> wrote:
> On Friday 29 August 2008, Arjan van de Ven wrote: > > > With this patch series, the internals of select() and poll() > > interfaces are changed such that they work on the nanosecond level > > (using hrtimers). The userspace interface for select() is in > > microseconds, for pselect() and ppoll() this is in nanoseconds. > > Nice work, seems a lot better thought through than my previous > attempt [1], which unfortunately never saw any reactions. > > > even though poll() (as opposed to ppoll()) only accepts milliseconds > > as userspace interface, the behavior will still improve because the > > current time no longer needs to be rounded up to the next jiffie, > > so on average a 500 milliseconds behavior improvement. > > That would be 500 microseconds I think. > > > I'd like to get rid of the jiffies timeout entirely over time, and > > only use hrtimers (makes the code a lot nicer) but that's for now > > a separate step, first I'd like to see how this change pans out. > > You mean entirely entirely getting rid of jiffies in the kernel, or > just with user facing interfaces like epoll_wait, rt_sigtimedwait etc?
I meant actually just in the select() and poll() code; right now it is sort of dual-brained, I'd like to eventually be able to get rid of that and just use hrtimers for select() and poll() always
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