[ntp:questions] Writing the drift file

David Taylor david-taylor at blueyonder.co.uk.invalid
Fri Mar 6 10:48:30 UTC 2015

On 06/03/2015 09:35, Harlan Stenn wrote:
> Folks,
> A while ago we got a request from the embedded folks asking for a way to
> limit the writing of the drift file unless there was a "big enough"
> change in the value to warrant this.
> Somebody came up with an interesting way to do this that involves
> looking to see how much the drift value has changed and only writing the
> value if the change was "big enough".
> By my read of the code and the comments:
> 1) it looks like the code is implementing something other  than what the
> comments want, and
> 2) what's described *or* implemented seems way more complicated than
> what we need.
> I'm wondering if we should just let folks specify a drift/wander
> threshold, and if the current value is more than that amount we write
> the file, and if the current value is less than that amount we don't
> bother updating the file.  If folks are on a filesystem where the number
> of writes doesn't matter, no value would be set (or we could use 0.0)
> and it's not an issue.
> Thoughts?

Sounds good to me.  But do you really mean "current value" or 
"difference from last written value"?

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