On 8 Jan 2006 at 15:04, Tom Van Baak wrote:

> You cannot divide timekeeping, time dissemination,
> into neat stages. In the 1960s if ten labs were told
> to offset their phase or frequency it affected only a
> handful of people or systems. Today when IERS
> announces a leap second, millions of machines,
> systems, and people are affected. Thankfully, most
> of them handle it OK.

Although, even now, the majority of consumer and business equipment
is not directly affected in any noticeable way; such machines usually
run on a local clock considerably less accurate than an atomic clock,
periodically re-synced (perhaps manually, perhaps automatically) to
an external time standard.  At each such re-syncing, the time may
need to be adjusted by a few seconds, or even a few minutes, due to
inaccuraccies in the local timepiece, so any leap second that may
have occurred since the last syncing will merely result in a 1-second
difference in the magnitude of this adjustment, not particularly
noticeable to the end users.  If some application (e.g., a database)
requires a timescale without discontinuities, the application might
need to be shut down for a few seconds to perform the time adjustment
(whether or not there is a leap second in the mix) in order to
prevent data corruption at the moment of the change.

== Dan ==
Dan's Mail Format Site: http://mailformat.dan.info/
Dan's Web Tips: http://webtips.dan.info/
Dan's Domain Site: http://domains.dan.info/

Reply via email to