From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: Can jitter also be smaller than amount of time or only bigger ?
Date: Wed, 29 Nov 2017 17:33:26 +0100
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To: Ran Shalit <ranshalit@gmail.com>
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On 2017-11-27 18:25:23 [+0200], Ran Shalit wrote:
> Hello,
Hi,

> When using rt linux, does it mean that the jitter is in both direction
> or only bigger than amount of time for wait ?
> For example, if we set periodic timer for 1msec, can it also be that
> we get the interrupt before the 1msec period ended ?

With or without RT: the timer must not fire too early. I can fire
_after_ the 1ms deadline but never before that.

> Thank you.
> Ran

Sebastian