Talk:2697: Y2K and 2038 - Revision history

141.101.99.198: Y2K still has a few teeth left.

2024-11-02T08:45:08Z

Y2K still has a few teeth left.

Kimmerin at 08:29, 17 November 2022

2022-11-17T08:29:54Z

172.71.126.41 at 17:17, 15 November 2022

2022-11-15T17:17:09Z

172.70.91.57 at 17:18, 14 November 2022

2022-11-14T17:18:27Z

172.70.86.61 at 14:44, 14 November 2022

2022-11-14T14:44:54Z

Philhower: 30 year mortgages

2022-11-14T14:12:04Z

30 year mortgages

141.101.107.157: ICYMI

2022-11-14T13:43:36Z

ICYMI

172.70.162.56 at 10:20, 14 November 2022

2022-11-14T10:20:03Z

172.70.130.154 at 06:52, 14 November 2022

2022-11-14T06:52:23Z

SDSpivey at 18:55, 13 November 2022

2022-11-13T18:55:43Z

← Older revision		Revision as of 08:45, 2 November 2024
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	"[https://www.explainxkcd.com/wiki/index.php?title=2697:_Y2K_and_2038&oldid=298667 I've never heard of anyone actually recompiling to a 33-bit integer format]" - that's not what was said, but it seems to be about programming so as to pack 33-bits of precision across (or within) whatever standard bit-boundaries the system normally provides for. Which is not so fanciful, and used to be a good creative coding practice, if done well. See 8x7bit to/from 8x7bit packing or unpacking (or as an in-transit stage), which was a regular requirement at one time (arguably still is, but mostly invisibly to the user, in the usually 6-bit rationalisation that is MIME). But the edit above doesn't preclude that interpretation, so just noting this here. [[Special:Contributions/141.101.107.157\|141.101.107.157]] 13:43, 14 November 2022 (UTC)		"[https://www.explainxkcd.com/wiki/index.php?title=2697:_Y2K_and_2038&oldid=298667 I've never heard of anyone actually recompiling to a 33-bit integer format]" - that's not what was said, but it seems to be about programming so as to pack 33-bits of precision across (or within) whatever standard bit-boundaries the system normally provides for. Which is not so fanciful, and used to be a good creative coding practice, if done well. See 8x7bit to/from 8x7bit packing or unpacking (or as an in-transit stage), which was a regular requirement at one time (arguably still is, but mostly invisibly to the user, in the usually 6-bit rationalisation that is MIME). But the edit above doesn't preclude that interpretation, so just noting this here. [[Special:Contributions/141.101.107.157\|141.101.107.157]] 13:43, 14 November 2022 (UTC)
		+
		+	''"systems built to operate this millennium handle years after 1999 correctly"'' Not necessarily. At least one UK bank (the one where I worked on Y2K) used "sliding century windows", where they pick a number X in the range 0 to 9, and any year where the YY of CCYY is greater than 10X is considered to be `this century', else last century, and in a few decades X can be moved along a bit. Not our team's decision, and by the time we heard about it it was far too late to complain about what a bloody stupid idea it was. The problem wasn't fixed properly; it was fixed cheaply. [[Special:Contributions/141.101.99.198\|141.101.99.198]] 08:45, 2 November 2024 (UTC)

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 ::[[1962|Zuckerbergs Army.]] --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 15:18, 12 November 2022 (UTC)
 :::The Legion of the Doomed [[Special:Contributions/172.70.162.56|172.70.162.56]] 10:20, 14 November 2022 (UTC)
+:Generation 😊 [[User:Kimmerin|Kimmerin]] ([[User talk:Kimmerin|talk]]) 08:29, 17 November 2022 (UTC)
 I've been unable to confirm this so I'm moving it here: A major problem had struck IBM mainframes on and after August 16, 1972 (9999 days before January 1, 2000) that caused magnetic tapes that were supposed to be marked "keep forever" instead be marked "may be recycled now."{{Actual citation needed}} [[Special:Contributions/172.71.158.231|172.71.158.231]] 07:37, 12 November 2022 (UTC)
 :I have heard that y2k problems showing up in 1970 in calculations for thirty-year mortgages. [[User:Philhower|Philhower]] ([[User talk:Philhower|talk]]) 14:12, 14 November 2022 (UTC)

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 :::{{w|Binary-coded decimal}}... Loads of interesting uses (including precision decimal fractions), but of course largely fallen out of favour for various technical and logistial reasons.  [[Special:Contributions/172.70.86.61|172.70.86.61]] 14:44, 14 November 2022 (UTC)
 :The first computerised passport system for the UK had a y2K issue. In fact, it was designed in, because it was supposed to be replaced before 1999. Unfortunately, progress with its replacement was running late. We thought that we could get away with two digits for certain dates because the software was going to be thrown away before the end of 1999. And yes, two digit years were common in COBOL programs because decimal numbers coded using ASCII or EBCDIC were the default for numeric data. [[User:Jeremyp|Jeremyp]] ([[User talk:Jeremyp|talk]]) 15:32, 13 November 2022 (UTC)
 :1. Having done programming since 1966, I know that much data was stored on 80-character cards (and way before that year and the IBM System/360) and using 2 characters (2.5% of the card) to store the "19" was not acceptable. As processes moved into the tape and disk world, human nature tended to not expand the field to 4 characters (the future is a long way off until, suddenly, it isn't). [[Special:Contributions/172.70.178.65|172.70.178.65]] 07:57, 13 November 2022 (UTC)

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 Somewhere there is an essay about the unexpected synergy between the Y2K bug and the burgeoning open source movement, which may or may not be useful for the explanation. [[Special:Contributions/172.70.214.243|172.70.214.243]] 20:18, 11 November 2022 (UTC)
 :https://www.livehistoryindia.com/story/eras/india-software-revolution-rooted-in-y2k is a fascinating essay too. [[Special:Contributions/172.70.214.151|172.70.214.151]] 21:03, 11 November 2022 (UTC)
 :I wouldn't be surprised if there's such an essay, but I suspect it's more of a coincidence. The late 90's was also when the Internet was really taking off, and that may be more of a contributor. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 23:04, 11 November 2022 (UTC)
 ::All involved what epidemiologists call coordinated or mutually reinforcing causes, IMHO. [[Special:Contributions/172.71.158.231|172.71.158.231]] 01:41, 12 November 2022 (UTC)
 Speaking of which, what comes after Generation Z? Generation AA? ZA? Z.1? Help! [[Special:Contributions/172.70.214.243|172.70.214.243]] 07:24, 12 November 2022 (UTC)
 :{{w|Generation Alpha}} [[Special:Contributions/172.69.34.53|172.69.34.53]] 07:27, 12 November 2022 (UTC)

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 ::Sometimes the "savings" of storing data in a compact form are exceeded by the "cost" of having to convert it between the convenient-to-use form and the compact form.  I used to work on a system that used 32-bit words for all data types: characters, shorts, longs.  When we started running out of space, we "manually" packed our data, stuffing multiple shorts and bytes into words.  But in some cases, the additional code needed to pack/unpack would have taken more space than what we'd have saved in the data, without even looking at the processing time cost. [[User:BunsenH|BunsenH]] ([[User talk:BunsenH|talk]]) 05:52, 13 November 2022 (UTC)
 ::Not sure about storing each digit as a *character*, but IBM mainframes have supported packed decimal formats where each decimal digit was stored in a 4-bit nibble. That format can give more intuitive results from decimal fraction arithmetic for applications such as currency. But, I've heard of the same format being used for integer applications such as page numbers, etc because it was familiar and readable on hex dumps. [[User:Philhower|Philhower]] ([[User talk:Philhower|talk]]) 14:12, 14 November 2022 (UTC)
 :The first computerised passport system for the UK had a y2K issue. In fact, it was designed in, because it was supposed to be replaced before 1999. Unfortunately, progress with its replacement was running late. We thought that we could get away with two digits for certain dates because the software was going to be thrown away before the end of 1999. And yes, two digit years were common in COBOL programs because decimal numbers coded using ASCII or EBCDIC were the default for numeric data. [[User:Jeremyp|Jeremyp]] ([[User talk:Jeremyp|talk]]) 15:32, 13 November 2022 (UTC)

← Older revision		Revision as of 13:43, 14 November 2022
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	''"an actual program or OS that stored the year as two characters"'' In years 2000-2002, it was common to see dates on web-pages showing as "19100". I/we always assumed the 19 was hard-coded, the 1-99 was a script, just concatenated. ''PRR'' [[Special:Contributions/172.70.130.154\|172.70.130.154]] 06:52, 14 November 2022 (UTC)		''"an actual program or OS that stored the year as two characters"'' In years 2000-2002, it was common to see dates on web-pages showing as "19100". I/we always assumed the 19 was hard-coded, the 1-99 was a script, just concatenated. ''PRR'' [[Special:Contributions/172.70.130.154\|172.70.130.154]] 06:52, 14 November 2022 (UTC)
		+
		+	"[https://www.explainxkcd.com/wiki/index.php?title=2697:_Y2K_and_2038&oldid=298667 I've never heard of anyone actually recompiling to a 33-bit integer format]" - that's not what was said, but it seems to be about programming so as to pack 33-bits of precision across (or within) whatever standard bit-boundaries the system normally provides for. Which is not so fanciful, and used to be a good creative coding practice, if done well. See 8x7bit to/from 8x7bit packing or unpacking (or as an in-transit stage), which was a regular requirement at one time (arguably still is, but mostly invisibly to the user, in the usually 6-bit rationalisation that is MIME). But the edit above doesn't preclude that interpretation, so just noting this here. [[Special:Contributions/141.101.107.157\|141.101.107.157]] 13:43, 14 November 2022 (UTC)

← Older revision		Revision as of 06:52, 14 November 2022
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	:2. I actually saw a Y2K failure. It occurred at the beginning of 1999 when a job scheduling program scheduled a job for the year 1900 because it was always keeping the schedule active a year in advance. The scheduling software had actually been fixed but the upgraded version had not been installed yet, so there was no significant outage. [[Special:Contributions/172.70.178.64\|172.70.178.64]] 08:02, 13 November 2022 (UTC)		:2. I actually saw a Y2K failure. It occurred at the beginning of 1999 when a job scheduling program scheduled a job for the year 1900 because it was always keeping the schedule active a year in advance. The scheduling software had actually been fixed but the upgraded version had not been installed yet, so there was no significant outage. [[Special:Contributions/172.70.178.64\|172.70.178.64]] 08:02, 13 November 2022 (UTC)
		+
		+	''"an actual program or OS that stored the year as two characters"'' In years 2000-2002, it was common to see dates on web-pages showing as "19100". I/we always assumed the 19 was hard-coded, the 1-99 was a script, just concatenated. ''PRR'' [[Special:Contributions/172.70.130.154\|172.70.130.154]] 06:52, 14 November 2022 (UTC)