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Date: Sat, 10 Mar 2007 21:44:22 -0800 (PST)
From: Davide Libenzi <davidel@xmailserver.org>
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To: Linus Torvalds <torvalds@linux-foundation.org>
cc: Nicholas Miell <nmiell@comcast.net>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [patch 6/9] signalfd/timerfd v1 - timerfd core ...
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On Sat, 10 Mar 2007, Linus Torvalds wrote:

> > Actually, the only place where I can find the itimerspec usefull, is 
> > indeed with TFD_TIMER_SEQ. In cases where you want you clock starting at a 
> > given time (it_value) *and* with the given frequency (it_interval).
> 
> .. and this is where itimerspec is even better: once you have absolute 
> time, *and* a process that might miss ticks (because it does something 
> else), the "absolute time start + interval" thing can avoid drifting 
> (which a "relative interval" has a really hard time doing).
> 
> So if you want a "timer tick every second, *on* the second" kind of 
> interface, you really do want a absolute time starting point, and then a 
> fixed interval. Two different times.

Alrighty, I'll use a itimerspec ...



- Davide