On 2018-8-19 00:58, Brian Inglis wrote:
On 2018-08-17 13:13, Tom Lane wrote:
Howard Hinnant <howard.hinnant@gmail.com> writes:
On Aug 17, 2018, at 3:53 AM, Paul Eggert <eggert@cs.ucla.edu> wrote:
"The biggest hurdle in Japan to putting daylight saving time in place is the cost and workload required to adjust computer systems. Professor Tetsutaro Uehara of Ritsumeikan University, a specialist in information systems, estimates that it would take about four years and hundreds of billions of yen to do just that. Let’s send ‘em a bill. ;-) I rather imagine the professor has a point. Yeah, code that uses tzdb would be easy to update. But Japan is likely chock-full of locally grown code that has never had to cope with any situation other than "JST = UTC+9", and probably hasn't got any generality whatsoever about its timestamp handling.
I doubt the bewildered professor has enough background in industrial, commercial, and retail software development and deployment practices, infrastructure and apps to make a reasonable estimate. Recall the posts we've had about squishing and updating tzdbs in firmware: major embedded libraries support tzdb and locales (although they can usually be omitted), get contributions from the chip makers who use them, and BSD and TZ code can be freely leveraged to support DST. As usual, the main problem will be updating or replacing software and systems not designed to be updated because of assumptions: like pre-Y2K, and 2005-2007 for the North American DST dates rule changes.
-- Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada
According to slideshows published by the professors, the point is that, - In most other countries, there are DST from before computers and connected machines become widespread, so most of foreign systems have designed with summer time in mind, however same cannot be said to Japan, and there are no recent examples of developed country that move into DST from no DST so there are no example of how far fetched could it become - 4-5 years time given is the time to adjust important national and regional system as well as systems of businesses that support important infrastructure systems. From detecting the necessity, to obtain the funding, design, application of fix, test, to actual implementation, he estimated 4-5 years would be needed while private companies would need at least 3. And then in individual home it's estimated there will also have many unsupported machines that cannot be forced to replace so it would probably take something like a ten year cycle to replace them all. - The estimated cost is based on the need of checking and adjusting all the systems, which he estimated that 30 billion yen would be needed just to detect and fix problems in important infrastructure systems and private corporates will spend more than that to do the same to their own system. And then he mentioned that when people are busy fixing legacy systems to support summer time, they will not have any extra efforts that can be used to catch up with new innovative trends across the word, like AI, IoT, Big data. And that's not to mention workers in Japan already have extra workloads like supporting the new era name and account for the sales tax hike. - Even for systems that have been set to automatically update, it is still not sure whether they are using a correct automatic setting that can actually update accordingly (especially with the proposal including double summer time) - If Y2K situation is anything to learn from, then that is there will be a lot of malware that will spread in the name of 'help fixing your "____" to support DST' when all kind of patches for different machines pop up, and that might even enable cyber terrorism