On Tue, Sep 22, 2015 at 12:48 AM, Paul Eggert <eggert@cs.ucla.edu> wrote:

On 09/21/2015 01:41 PM, Deborah Goldsmith wrote:

when you’re pushing bits to hundreds of millions of devices you need to do thorough testing. There are also release cycles, as users don’t like to be bombarded with requests to update their devices too frequently

Red Hat and Ubuntu have tens of millions of users.  This difference in scale does not explain why Apple can take over six months to propagate a small change to time zone data, whereas Ubuntu can do it in a few hours.  More plausibly, the difference comes from Apple bundling time zone data into its operating systems and requiring a full test cycle and OS upgrade in order to install fixes, whereas Red Hat, Ubuntu, etc. treat time zone data separately and routinely issue minor updates for just a few small files, which can be tested separately.

The incremental approach is better for end users and for developers and for testers, and one way or another Apple needs to change its software process to support it.  Any such change is needed regardless of what tzdata does, because governments typically don't notify us a year in advance.  Of course a development-organization battleship cannot turn on a dime, but that's OK; there's no rush, as in the meantime you can cherry-pick changes from the experimental version on Github as needed.

If there is impact on IANA from releasing more frequent updates

There is some impact on IANA, though not much: they are mostly just hosting the data.  There is more impact on me, and on development organizations downstream from tzdata.  Every time I do a release, I check over the distribution; some of this work is automated and some is not.  My work is volunteer and my time is limited.  The situation is similar for many other downstream developers.  Most do not have the resources of Ubuntu or Red Hat, much less Apple or Google.