Re: Finegrained a/c/mtime was Re: Directory notification problem

From: Andi Kleen (ak@suse.de)
Date: Wed Oct 03 2001 - 16:26:09 EST


On Wed, Oct 03, 2001 at 11:15:04AM -0400, Alex Larsson wrote:
> Is a nanoseconds field the right choice though? In reality you might not
> have a nanosecond resolution timer, so you would miss changes that appear
> on shorter timescale than the timer resolution. Wouldn't a generation
> counter, increased when ctime was updated, be a better solution?

Near any CPU has a cycle counter builtin now, which gives you ns like
resolution. In theory you could still get collisions on MP systems,
but window is small enough that it can be ignored in practice.

-Andi
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