Daylight Saving Time (DST) within one country

[Superdeboer]

Any intelligent user can see that no matter what time of the year it is, 10:00am GMT is always 10:00am GMT. Just because you've changed to using a different timezone for this particular month the time in GMT is still the same.

Any Dutch user doesn't give a damn about GMT, because GMT does not take DST into account. That's what I've been saying all the time. We don't live in GMT, we're not computers you see... My watch says it's 12:39h now, not 10:39h GMT+1 +DST. As long as my board doesn't cross borders of timezones, GMT won't give *any* advantage to me, don't you see that after reading this whole discussion?

So that means to get things displayed the way you want a lot of extra calculations have to be made at the time the data is displayed. This could slow page times down a fair bit.

It won't cause 'a lot' of extra calculations. I need a list of dates on which DST changes in my country. Based on that, I only have to make a function that checks if DST is true or false. If DST is true, then put posttime into a new column called local_post_time in GMT + 3600. If DST is false, put posttime into that column without 3600 extra seconds. That's all... won't be too hard I think. *If* there might occur any slowing down of some pages (which I doubt), it will happen at the moment of posting, not at the moment of viewing a topic.

So you want the devs to spend a lot of time implementing a new feature that alters the way the board works in a way that would be detrimental to the performance of the board if switched on and you request the feature in the wrong place and in a way that makes it sound like the board is doing something wrong currently .... and you're suprised when people aren't immediately saying what a brilliant suggestion it is?

I conclude that you've only read the last few reactions. If you would have read the whole thread, you would've seen that this topic is not a plain feature request, but an attempt to discuss the current way of displaying times, which in my opinion is too limited for some users, apparently not including you.
Also you would have noticed that I already gave in and said that I will first try this things for myself, by writing a mod in the best way I can. Again: the argument of saying that an option like this *might* effect performance in a negative way, doesn't convince me at all. So does a useless thing like "who's online" that appears on every page now. But just the fact that I don't need it, doesn't mean that no one else will like it. It's the same way with this thing: I know for sure that this mod will be very popular when I publish it on Dutch phpBB forums. That *you* don't see the advantages of it, doesn't mean that it's unusefull to a lot of other people and therefore not important enough to offer a little performance to it. But then again: if it's an option... why would you turn it on if you're so fond of performance and don't like the option? OK, you won't turn it on... but that doesn't give you the right to oppose against it to obstruct the implementation of such a feature for people who do like it. It wouldn't harm you if it's implemented and you wouldn't use it.

[Mvastango]

So that means to get things displayed the way you want a lot of extra calculations have to be made at the time the data is displayed. This could slow page times down a fair bit.

So you want the devs to spend a lot of time implementing a new feature that alters the way the board works in a way that would be detrimental to the performance of the board if switched on and you request the feature in the wrong place and in a way that makes it sound like the board is doing something wrong currently .... and you're suprised when people aren't immediately saying what a brilliant suggestion it is?

The way I see it at least, you can use GMT as a good way to store the data, since it's pretty much a universal standard. GMT is bad from a usabiltiy standpoint however, to make available to the end user. I would never expect the users of a forum to know what a GMT is or how their time zone differs from that. I remember the first time I signed up for a php forum - I picked a random time zone, and kept resetting it until the time on the front page was correct. Users shouldn't have to go through that. Even the users who have already used another phpBB board or two will find they have to log in to the other board to copy the settings when they register for a new one. So technically, I don't look at this as a bug, but as a UI problem. The board definitely is returning the time in GMT - 4 (for me) but it does so even for posts that were posted while the time here in New York was equal to GMT - 5. The only solution I see is a drop-down list of cities in the UCP and then the time being computed for each date displayed. It may have varying or negative effects on server performance, but it's certainly the most accurate and user-friendly interface to time zones.

[Klors]

I read the entire thread before I posted, thanks. I'm also pretty sure that psoTFX has spelled this issue out before somewhere in a request to have the board to auto-detect whether or not to change to displaying times in daylight saving time formats during those times of the year, but I'm too lazy to look, as it also appears are you. So, okay, I'll spell everything out for you. I'm ignoring your server clock because you've not really spelled out how that affects your board times.

Any Dutch user doesn't give a damn about GMT, because GMT does not take DST into account. That's what I've been saying all the time. We don't live in GMT, we're not computers you see... My watch says it's 12:39h now, not 10:39h GMT+1 +DST. As long as my board doesn't cross borders of timezones, GMT won't give *any* advantage to me, don't you see that after reading this whole discussion?

The point wasn't that times should be in GMT, you can already choose what local time to display in. In my example you can replace GMT with whatever timezone you like, it's not relevant. Or if you were alluding to having a 'real life' time setting then you're equally far off the mark.

I'll explain the point I was making shall I? Let's use a fictional timezone, FTZ with a daylight savings time one hour ahead called STZ and let's say it changes back from STZ to FTZ at 02:00 on the 20th September (note: that's 2 o'clock on the morning of September 20th). So at 01:59 STZ on September 20th, in 60 seconds time it will be 01:00 FTZ.

So, if you post a message at 13:37 STZ sometime in August saying "Subject: Hey I'm posting at a leet time dudes!". If you then dutifully changed your local time setting in your profile back to FTZ in September. When you next look at that post, it will be odd because it will appear to have been posted at 12:37, not so 'leet'. (Indeed, if you were not such a dilligent profile-timezone-changer it would probably already show as a different time to your local time when you posted it)

This, we know, is correct behaviour. So I assume you're not arguing that point.

The point I have assumed you are trying to make is that a post made on a server in this fictional timezone at 13:47 STZ should always be displayed as being made at 13:47, even if we're looking at it in the FTZ portion of the year. Correct?

So that leads me to believe you'd like the option to have everything displayed in the local time it was posted at, always, as a setting in the control panel? Well, then that sounds like a feature request to me.

It won't cause 'a lot' of extra calculations. I need a list of dates on which DST changes in my country. Based on that, I only have to make a function that checks if DST is true or false. If DST is true, then put posttime into a new column called local_post_time in GMT + 3600. If DST is false, put posttime into that column without 3600 extra seconds. That's all... won't be too hard I think. *If* there might occur any slowing down of some pages (which I doubt), it will happen at the moment of posting, not at the moment of viewing a topic.

Though I'd imagine the collaborative efforts of the phpBB team could come up with a better solution than I could over the time of writing that post. The only solutions to the request that I could think of, such as including a local time in the db as well as the timestamp, or calculating the local posted time from the timestamp for each post at display time, involve redundant data and/or extra processing.

Hence, why I mentioned a performance decrease, due to the bigger db size and a little processing or extra processing at display time. Probably not that dramatic for the local board, but going in the wrong direction and maybe quite noticeable on the bigger boards (that field would still be present even if the feature were turned off).

I conclude that you've only read the last few reactions.

Well, then you concluded in error.

If you would have read the whole thread, you would've seen that this topic is not a plain feature request, but an attempt to discuss the current way of displaying times, which in my opinion is too limited for some users, apparently not including you.

I fail to see how doing things properly is limited...

Also you would have noticed that I already gave in and said that I will first try this things for myself, by writing a mod in the best way I can. Again: the argument of saying that an option like this *might* effect performance in a negative way, doesn't convince me at all. So does a useless thing like "who's online" that appears on every page now.

"an option like this". So it's a feature request then?

But just the fact that I don't need it, doesn't mean that no one else will like it. It's the same way with this thing: I know for sure that this mod will be very popular when I publish it on Dutch phpBB forums. That *you* don't see the advantages of it, doesn't mean that it's unusefull to a lot of other people and therefore not important enough to offer a little performance to it. But then again: if it's an option... why would you turn it on if you're so fond of performance and don't like the option? OK, you won't turn it on... but that doesn't give you the right to oppose against it to obstruct the implementation of such a feature for people who do like it. It wouldn't harm you if it's implemented and you wouldn't use it.

I didn't oppose it. I thought it was strange that you were getting so worked up over a feature request that I still fail to see the logic in implementing, said so and then told you to post it on the sourceforge feature request tracker where it belongs.

[Superdeboer]

So, if you post a message at 13:37 STZ sometime in August saying "Subject: Hey I'm posting at a leet time dudes!". If you then dutifully changed your local time setting in your profile back to FTZ in September. When you next look at that post, it will be odd because it will appear to have been posted at 12:37, not so 'leet'. (Indeed, if you were not such a dilligent profile-timezone-changer it would probably already show as a different time to your local time when you posted it)

Well, thanks for repeating the exact example I mentioned a few times now. This behaviour is only correct when you're reasoning from the premise that a timesystem that doesn't care for DST will give the correct time. My point of view is that it's wrong in that respect, because in theory it will return the most universal time to me, but practically it's just wrong. It *is not* correct. I am facing DST in my country, so ignoring that will return the *wrong* results.

The point I have assumed you are trying to make is that a post made on a server in this fictional timezone at 13:47 STZ should always be displayed as being made at 13:47, even if we're looking at it in the FTZ portion of the year. Correct?
So that leads me to believe you'd like the option to have everything displayed in the local time it was posted at, always, as a setting in the control panel? Well, then that sounds like a feature request to me.

Then again I think you haven't been reading very well, but you're merely labeling this topic for yourself as a feature request and afterwards say: hey look, it's labeled 'feature request'. In my very first sentence I said: "It is hard for me to understand why the developers team has chosen to deal with Daylight Saving Time (DST) only by adding an extra userpreference." The point I was trying to make when I started this discussion, is that it seems odd to me that the phpBB development team says in their feature list that phpBB 2.1 now deals with DST, when in fact it doesn't. The effect of what they've created now, could as well be reached by putting the timezone one step ahead during DST, but doesn't solve the real problem of post times still being incorrect, as you just illustrated yourself. That's why I said: you're planning to do a feature release, but instead of truly solving this issue, you're implementing an option in user profile that shouldn't even be called a feature IMO. That's not a feature request, that's only discussing this so called new feature. Which could be left out in my opinion, because when this is the only thing to deal with DST, I could easily go and set my timezone to GMT +2 instead of GMT +1, when it's DST. As I sead before: 'GMT' doesn't mean anything for me as a human user, so I even don't care if my timezone must be set to GMT +1 or GMT +8, although my actual time zone is GMT +1. And still... still the post times of half a year will appear incorrect, whatever I do.

Hence, why I mentioned a performance decrease, due to the bigger db size and a little processing or extra processing at display time. Probably not that dramatic for the local board, but going in the wrong direction and maybe quite noticeable on the bigger boards (that field would still be present even if the feature were turned off).

I think you may be correct at that point.

I fail to see how doing things properly is limited...

This is a tough way of discussing things. You're talking from the starting point that this way the handling of the post times is done in a proper way. I constantly say that that doesn't apply to people who live in a country where DST is used, because it's inaccurate for half of the post times. How could a system that in some cases (DST countries) displays 50% of all post times *wrong* be a proper way of handling the time issue? There is no absolute and only proper way to handle the time. Pretending that there is one and that it's the one that's currently used, is simply not fair, because my board practically gives me a different experience. Sure, time handling based on the GMT unix timestamps is the most common and the most universal alternative. But that doesn't prove that it's the most ideal one for everyone. And as argumented above, it surely doesn't always return the most correct results.

[Graham]

The problem that I think you are missing is that handling it the way you want it has strange side effects.

For example if I post at 01:40 DST and again at 01:20 non-DST on the morning where the clocks change, which post displays first? If you display them in the order they were posted it looks odd, if you display them in the order of the time, you have a reply before the original post.

The way things are handled may not be what you want, but it does give a consistancy to the data.

To my knowledge, no forum software does what you want these days (well I can think of one that sort of does it, but then it doesn't support DST at all) because it is messy.

I think it is safe to assume from comments elsewhere on DST handling that it won't make it into 2.2, and that if you want it, it will need to be a MOD.

[hater]

Other problems that come about from this method are already prominent in phpBB2.0x and openly visible when using a birthday modification which is already built into 2.x, and a calendar/event modification which means time sensitive events can frequently be 1 hour off.

Also the above noted problem of posts being 1 hour fore or aft due to the time-shift can be bothersome, however they really only exist for the minimal amount of posts created during the 1 hour in the fall that overlaps.

Funny, but I guess I just learned to deal with this is as a limitation of trying to create a forum system that worked "well for all" rather than "great for some" which I have nothing against.

[Klors]

This is a tough way of discussing things. You're talking from the starting point that this way the handling of the post times is done in a proper way. I constantly say that that doesn't apply to people who live in a country where DST is used, because it's inaccurate for half of the post times. How could a system that in some cases (DST countries) displays 50% of all post times *wrong* be a proper way of handling the time issue? There is no absolute and only proper way to handle the time. Pretending that there is one and that it's the one that's currently used, is simply not fair, because my board practically gives me a different experience. Sure, time handling based on the GMT unix timestamps is the most common and the most universal alternative. But that doesn't prove that it's the most ideal one for everyone. And as argumented above, it surely doesn't always return the most correct results.

Okay, i can see I'm still not making that point clearly.

That system does take into account DST times and is "correct". I'll try and explain why I say that better. You probably know some of what I'm explaining, but I'm just trying to be clear.

When you post your post, you post it at a single global time, the timestamp. This is needed to keep posts in their correct order and to do time-dependant functions by the computer.

That timestamp is then translated into whatever time is displayed on the board. So if you're viewing a FTZ board it should be displayed in FTZ, so that it appears more like people would expect to see a time. That timestamp is always the same, only the relative offset changes when you alter the local viewing time.

So when you post, you are actually posting at both 19:05 FTZ and 20:05 STZ and all the other offset times.

When you change that local board time to view at, all of the posts change because you are just switching to look at them from a different timezone. The fact that it's a daylight savings time is of no relevance, it could be any timezone.

Taking a real life look at this, the situation is exactly the same as if I live in GMT and someone else lives in Europe on the GMT+1 timezone. If both of us have our profiles set up for our local time, we'll both view the posting time as different.

All you are doing when you go to daylight savings time is changing timezone, why would it be any different.

But I get the feeling that you already know most of this which is why the request seems all the more bizarre. It seems to me to be kludging an accurate system.

Also, if you're saying the board's system is wrong, then you are mistaken. I'm not commenting on its user-friendliness, here. If you aren't saying it's wrong then it looks to me like a feature request.

[Mvastango]

The problem that I think you are missing is that handling it the way you want it has strange side effects.

For example if I post at 01:40 DST and again at 01:20 non-DST on the morning where the clocks change, which post displays first? If you display them in the order they were posted it looks odd, if you display them in the order of the time, you have a reply before the original post.

Well ideally, the times in the database would be stored in some common standard format, seperate from the time zones set on the board (i.e. GMT). Then, as the times are displayed, they would be converted into the user's timezone with applicable DST (or the default time zone if a user isn't logged in). All times should be shown in the time zone of the viewer. In essense, the code is figuring out, 'When this was the GMT Timestamp, what was the time in New York, USA?' where the user is in New York. Since all times would be shown in the same time zone it wouldn't look weird. Looking at the CVS code, it doesn't seem like it would be a major undertaking to program. All that would really need to be modified would be the code that displays the dates and then a field would have to be changed in the UCP. Since I haven't actually programmed it (nor do I have a production board running 2.2 to try it out on), I don't have a clear idea of the performance hits related to this.

[Mvastango]

The fact that it's a daylight savings time is of no relevance, it could be any timezone.

Taking a real life look at this, the situation is exactly the same as if I live in GMT and someone else lives in Europe on the GMT+1 timezone. If both of us have our profiles set up for our local time, we'll both view the posting time as different.

All you are doing when you go to daylight savings time is changing timezone, why would it be any different.

But I get the feeling that you already know most of this which is why the request seems all the more bizarre. It seems to me to be kludging an accurate system.

Also, if you're saying the board's system is wrong, then you are mistaken. I'm not commenting on its user-friendliness, here. If you aren't saying it's wrong then it looks to me like a feature request.

The fact that it's daylight savings does have relevance. If I live in an area that observes DST, and it's currently the summer now, for all posts made in the winter, the time will be show to have been posted 1 hour off from the time they were actually posted. This is because my current GMT-Offset is applied to all posts uniformly, regardless of whether they were made in or out of DST.

[Superdeboer]

The fact that it's daylight savings does have relevance. If I live in an area that observes DST, and it's currently the summer now, for all posts made in the winter, the time will be show to have been posted 1 hour off from the time they were actually posted. This is because my current GMT-Offset is applied to all posts uniformly, regardless of whether they were made in or out of DST.

/me applauds for Mvastango. You really see my problem dude.

The problem is not the difference between timezones or the difference between GMT and my timezone. The problem is the difference between summer and winter, because in summer we have DST, so *on top of all timezone things* there comes one hour extra to get to the real and correct time.

@Klors:
Firstly I have to thank you for your patience in responding.

When you post your post, you post it at a single global time, the timestamp. This is needed to keep posts in their correct order and to do time-dependant functions by the computer.

I'm not sure, but is the timestamp really used to order the posts? I don't have that piece of code here right now, but wouldn't it be logical to use the post_id's for that? (Doing so would at least solve that problem when I'd write a mod to use local time, I guess.)

So when you post, you are actually posting at both 19:05 FTZ and 20:05 STZ and all the other offset times.

And that's where it goes wrong for me. When I post at 19:05 FTZ, it also has to be displayed as 19:05 during STZ, because it was posted at 19:05 and not at 20:05. It's not more complex than that. I understand your point of view, but I just don't agree with it.
If I understand you well, you see the timezone as a quite absolute value, and see the DST as a relative difference on top of that. For me DST is necessarily attached to the timezone. For you 19:05 FTZ is the same as 20:05 STZ whereas for me 19:05 FTZ must be the same as 19:05 STZ, *because* it's 19:05. I don't know if we can convince eachother, when having a different conception at this point.

All you are doing when you go to daylight savings time is changing timezone, why would it be any different.

In my opinion you don't. Going to DST means for me continuing to use the same timezone, but adding an extra hour to it, *only in the summer*. As long as you base your time displaying on GMT, wich does not add that extra hour only in summer (it wouldn't be possible, because it differs from country to country), you will never have the effect that I'm aiming at. Unless you do some calculations that use custom information about when DST takes effect and stuff.

I'll try to figure out what I can create for myself. Then I'll try to tune it to make it as universally useful as possible. When it's done, I'll post it somewhere as a MOD. I hope you'll be there to criticise it at that time. Maybe I can persuade you when you see it fully functioning.
But like I said in my early posts: when you're running a board with users from different timezones, it's clear to see that my problem is a minor one for you and it's more important for you to give the users the ability to set at least their different timezones correctly. In that case my problem is not your problem and you won't profit from the thing I'm planning to write.