[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: "svn diff" and "svn log" timestamp weirdness

From: John Peacock <jpeacock_at_rowman.com>
Date: 2005-08-31 20:39:05 CEST

Ben Collins-Sussman wrote:
> I suppose we could
> either (A) always store the svn:date property rounded off to the
> nearest second, or (B) when loading the svn:date property for
> comparison purposes, round it off to the nearest second (this would be
> in our rev_hunt() binary search algorithm...)

My 2 cents:

A) is better in the long run, because it doesn't perpetuate the illusion
that computer clocks are that accurate unless you are regularly syncing
with a reference clock; I've seen drift rates of seconds to minutes per
month. Just because someone decided to provide nanosecond precision
doesn't mean that your computer can provide meaningful data at that
level. Precision != accuracy.

B) is better for compatibility purposes, since it ignores existing
subsecond precision.

The best solution is to do both now; round to seconds when comparing,
but stop storing subsecond precision. When 2.0 comes out, change the
search code to stop rounding and perform a last rounding when updating
the repository.

John

-- 
John Peacock
Director of Information Research and Technology
Rowman & Littlefield Publishing Group
4501 Forbes Boulevard
Suite H
Lanham, MD  20706
301-459-3366 x.5010
fax 301-429-5748
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@subversion.tigris.org
For additional commands, e-mail: dev-help@subversion.tigris.org
Received on Wed Aug 31 20:41:38 2005

This is an archived mail posted to the Subversion Dev mailing list.