4 ms·

IPhone DST bug causing alarms to fail across Europe

22 points by Garbage 16y ago

rix0r 16y ago
Yup, this happened to me too this morning. I even checked specifically for this last night: I was figuring that Apple would internally store the time in UTC and that my alarm time would have changed to an hour later than the usual time. Wouldn't have been ideal but I could have understood that. But no, when I checked my alarm the (display) time was still 8:00 AM. This morning, I awoke for other reasons a little past 8 and my alarm hadn't gone off. Then, at 9, it did. For some reason, there is some mismatch between the display time and the actual time, although I couldn't imagine what it would be. I imagine there is some caching of information involved somewhere...
JofArnold 16y ago
I solve this by setting the TIMER to 8 hours as I go to bed. Then it doesn't matter what time the device "thinks" it is. As a bonus, I'm more likely to believe the value the next day. I do this because so many of my devices auto-update, fail to audo-update or just don't update at all I don't trust them any more :P
- kiba 16y ago
  I have no use for alarm clocks. Surprisingly, this work rather well. I was never late yet.
hitonagashi 16y ago
Hmm, I guessed(evidently wrongly) that the alarms were working by "if set to every monday, when alarm is called, increment the time till next alarm by a week". Good job that article pointed out that deleting and readding the alarm didn't fix anything.
DrJokepu 16y ago
It was quite funny to hear people's alarm clocks going off randomly this morning on the London Underground.
VBprogrammer 16y ago
Anyone know what model of iPhone this affects? My iPhone 3GS went off at the correct time this morning. I use a radio alarm as well in anycase.
- demallien 16y ago
  The problem only occurs if you have a repeating alarm that doesn't repeat every day. If it's non-repeating, or repeats every day, things work fine. For the record, my iPhone 3GS on iOS4.1 exhibited the behaviour this morning (hey, who cares, it's a public holiday in France... of course, it'll still cause problems tomorrow morning)
  - VBprogrammer 16y ago
    I should have said, it is set on weekdays.
i386 16y ago
For a company that survives on consumer confidence I find it incredible that Apple have not released a revision of iOS with an update to solve this issue. This is how good brands start to erode - if you cant have confidence in a conceivably simple feature of the product then its only one step away from not having any confidence in the product at all.
- yellowbkpk 16y ago
  It is incredibly difficult to get "time" features right, especially recurring alarm/timer features. Daylight savings time only makes it much, much harder. All 3 companies I've worked for have had relatively serious issues with time, time zone, and DST. The most serious being patient monitoring devices that did the "wrong thing" with timezones. All other devices on the network had to account for the problem because years and years of work had gone into validation on the code for this device. Instead of fixing it at the source, the company spent years of developer time working around it at the other end. Time is hard, so I'm not surprised Apple got it wrong. Thankfully, it's a relatively small usecase.
  - borism 16y ago
    Amazingly Linux and other Unixes (yeah, OSX too) "get" time quite well. Maybe Apple over-optimized iOS?
    - yellowbkpk 16y ago
      As difficult as it is to implement time correctly in the OS, I imagine the timer/alarm apps that Apple wrote don't use any OS features (beyond the "what time is it?" API) so all of the issues usually arise in application code.
    - mmt 16y ago
      The OS itself may, but apps don't always. The 2:30-localtime problem has been an awkward one for cron in the past.
  - sorbus 16y ago
djhworld 16y ago
I'm from the UK with an iPhone 4 and my alarm went off fine this morning. I haven't upgraded to 4.1 yet though, perhaps this is where the bug manifests itself
mattmcegg 16y ago
I am in USA and my alarm actually went off an hour EARLY today (iPhone 4 iOS 4.1). My alarm was set for 7:34am and my alarm went off at 6:34am. I reset my alarm for 8:30am and it went off at 7:30am. I assumed it was some weird daylight savings bug. anyone else in the US have this issue?

22 points by Garbage 16y ago

rix0r 16y ago

Yup, this happened to me too this morning. I even checked specifically for this last night: I was figuring that Apple would internally store the time in UTC and that my alarm time would have changed to an hour later than the usual time. Wouldn't have been ideal but I could have understood that. But no, when I checked my alarm the (display) time was still 8:00 AM. This morning, I awoke for other reasons a little past 8 and my alarm hadn't gone off. Then, at 9, it did. For some reason, there is some mismatch between the display time and the actual time, although I couldn't imagine what it would be. I imagine there is some caching of information involved somewhere...

JofArnold 16y ago

I solve this by setting the TIMER to 8 hours as I go to bed. Then it doesn't matter what time the device "thinks" it is. As a bonus, I'm more likely to believe the value the next day. I do this because so many of my devices auto-update, fail to audo-update or just don't update at all I don't trust them any more :P

kiba 16y ago
I have no use for alarm clocks. Surprisingly, this work rather well. I was never late yet.

hitonagashi 16y ago

Hmm, I guessed(evidently wrongly) that the alarms were working by "if set to every monday, when alarm is called, increment the time till next alarm by a week". Good job that article pointed out that deleting and readding the alarm didn't fix anything.

DrJokepu 16y ago

It was quite funny to hear people's alarm clocks going off randomly this morning on the London Underground.

VBprogrammer 16y ago

Anyone know what model of iPhone this affects? My iPhone 3GS went off at the correct time this morning. I use a radio alarm as well in anycase.

demallien 16y ago
The problem only occurs if you have a repeating alarm that doesn't repeat every day. If it's non-repeating, or repeats every day, things work fine. For the record, my iPhone 3GS on iOS4.1 exhibited the behaviour this morning (hey, who cares, it's a public holiday in France... of course, it'll still cause problems tomorrow morning)
- VBprogrammer 16y ago
  I should have said, it is set on weekdays.

i386 16y ago

For a company that survives on consumer confidence I find it incredible that Apple have not released a revision of iOS with an update to solve this issue. This is how good brands start to erode - if you cant have confidence in a conceivably simple feature of the product then its only one step away from not having any confidence in the product at all.

yellowbkpk 16y ago
It is incredibly difficult to get "time" features right, especially recurring alarm/timer features. Daylight savings time only makes it much, much harder. All 3 companies I've worked for have had relatively serious issues with time, time zone, and DST. The most serious being patient monitoring devices that did the "wrong thing" with timezones. All other devices on the network had to account for the problem because years and years of work had gone into validation on the code for this device. Instead of fixing it at the source, the company spent years of developer time working around it at the other end. Time is hard, so I'm not surprised Apple got it wrong. Thankfully, it's a relatively small usecase.
- borism 16y ago
  Amazingly Linux and other Unixes (yeah, OSX too) "get" time quite well. Maybe Apple over-optimized iOS?
  - yellowbkpk 16y ago
    As difficult as it is to implement time correctly in the OS, I imagine the timer/alarm apps that Apple wrote don't use any OS features (beyond the "what time is it?" API) so all of the issues usually arise in application code.
  - mmt 16y ago
    The OS itself may, but apps don't always. The 2:30-localtime problem has been an awkward one for cron in the past.
- sorbus 16y ago

djhworld 16y ago

I'm from the UK with an iPhone 4 and my alarm went off fine this morning. I haven't upgraded to 4.1 yet though, perhaps this is where the bug manifests itself

mattmcegg 16y ago

I am in USA and my alarm actually went off an hour EARLY today (iPhone 4 iOS 4.1). My alarm was set for 7:34am and my alarm went off at 6:34am. I reset my alarm for 8:30am and it went off at 7:30am. I assumed it was some weird daylight savings bug. anyone else in the US have this issue?