tungwaiyip.info

home

about me

links

Blog

< September 2016 >
SuMoTuWeThFrSa
     1 2 3
4 5 6 7 8 910
11121314151617
18192021222324
252627282930 

past articles »

Click for San Francisco, California Forecast

San Francisco, USA

 

Let's meet at 1am

My work needs me to setup computer system to work across the globe. A key issue is to have a common time reference. This gets tricky because of time zone. Just saying 12pm is imprecise. Which time zone is 12pm reference to? Is it 12pm in San Francisco? Or 12pm in London? Another complication is day light saving adjustment, which make time measure more irregular.

The standard practice is to use Coordinated Universal Time (UTC), i.e. Greenwich Mean Time. So everyone across the globe has a reference to the same standard time. Having a standard reference is great for computer system. But for us software engineers it is another quantity to juggle with. I often have to track time across systems. If the system responses something like 14:22, it is still hard to make sense of. Is it this afternoon? This morning? Or sometime in the future? Translating between local time and UTC is often necessity for me. But it is much harder to do mentally compares to, say translating between metrics and imperial unit.

One tip is I added a clock of Reykjavik, Iceland time on my cellphone. Iceland time happens to match UTC and Icelanders do not mess with daylight saving time. This gives me a easy read of current UTC time (8pm now, which is 1pm San Francisco time.)

I have a colleague who argues strongly that the entire world should adopt UTC time in actual daily use and do away with time zone. Standardization is probably very important for him. How practical is this for regular people? To this I said, let's have a meeting at 1am, UTC time (it is 6pm for your reference).

2016.09.08 comments

 

 

blog comments powered by Disqus

past articles »

 

BBC News

 

Trump rejects proposal for Russia to interrogate US citizens (19 Jul 2018)

 

New Brexit Secretary Dominic Raab vows to 'intensify' talks (19 Jul 2018)

 

Burberry burns bags, clothes and perfume worth millions (19 Jul 2018)

 

Zuckerberg in Holocaust denial row (19 Jul 2018)

 

Egypt sarcophagus: Mystery black tomb opened in Alexandria (19 Jul 2018)

 

Would you choose to sleep with the fishes? (19 Jul 2018)

 

Macron aide Benalla in French probe for beating protester (19 Jul 2018)

 

Trevor Noah defends 'Africa won the World Cup' joke (19 Jul 2018)

 

US faces retaliation if car tariffs go ahead (19 Jul 2018)

 

India Netflix actor Rajshri Deshpande 'disgusted by porn star label' (19 Jul 2018)

more »

 

SF Gate

 

Facebook to remove misinformation that leads to violence (19 Jul 2018)

 

Ship traffic, July 20 (19 Jul 2018)

 

EBay lays off nearly 300 Bay Area employees (19 Jul 2018)

 

Ship traffic, July 18 (18 Jul 2018)

 

Business News Roundup, July 19 (18 Jul 2018)

 

Settlement rejected in McDonald’s franchisee case (18 Jul 2018)

more »


Site feed Updated: 2018-Jul-19 15:00