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Leap second causing Linux server crashes?

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Re: Leap second causing Linux server crashes?

#51
I was logged on to a couple of CentOS 6 servers when I saw this happen, and on each one the Java processes went absolutely haywire. Everything else seemed to work fine.

I attempted to fix with adjtimex and the script in the linked question, but to no avail, in the end having to restart them all instead. After that, all was good again.

Re: Leap second causing Linux server crashes?

#52
post #32

Not surprising. In spite of all press that Y2K was just a silly waste of money, its events like these that makes me suspect it would have been a much bigger deal if everyone had ignored it and fixed it after things where shown to break.

A lot of engineers[1] spent a lot of time successfully fixing Y2K bugs. Because nothing well known blew up, many people wrongly assumed that Y2K was never a real problem to begin with. [1] I moved a Fortune 100 manufacturing company's database off an ancient mainframe that would've been disastrous come Y2K. It went smoothly and was thus a thankless job. They paid well though (mid six figures - those were the days).

When people say mid-six figures, do they mean 500k? Or 150k?

Re: Leap second causing Linux server crashes?

#53

Not surprising. In spite of all press that Y2K was just a silly waste of money, its events like these that makes me suspect it would have been a much bigger deal if everyone had ignored it and fixed it after things where shown to break.

Why does everyone always say Y2K wasn't an issue ? I'm sure there were a lot of consultant making too much money with little work - however _alot_ of bug fixes were done, that would have caused problems. So because it was taken seriously , stuff were fixed and issues didn't happen because of that. Personally, I fixed 3 Y2K bugs back then, 2 of them would have brought down a rather critical business support to simply…

"Why does everyone always say Y2K wasn't an issue?"

From the outsider's perspective, it is indistinguishable from any number of other putative disasters that required lots of money to fix, yet didn't come to pass... in some cases including putative disasters in which the money wasn't spent and the disaster didn't happen anyway.

I have the insider's perspective and I agree that it is the more accurate, that Y2K was, if not necessarily going to end the world, certainly a bad thing and was largely averted through effective engineering. But I can still see how from the outside it sure doesn't look that way.

Re: Leap second causing Linux server crashes?

#54

I was logged on to a couple of CentOS 6 servers when I saw this happen, and on each one the Java processes went absolutely haywire. Everything else seemed to work fine. I attempted to fix with adjtimex and the script in the linked question, but to no avail, in the end having to restart them all instead. After that, all was good again.

I just had the exact same experience.

Re: Leap second causing Linux server crashes?

#56

2012. and we still have problems keeping track of time. This is both fascinating and scary. P.S. for people wanting to know more this video is simple to understand but really amazing http://www.youtube.com/watch?v=xX96xng7sAE

2012 and we still don't really know what time is. The fact that we can keep track of it, even with all the problems, is quite amazing.

Physics perfectly well knows what time is. This is an issue with keeping track of time in terms of seconds, minutes, hours and days, and has nothing to do with not knowing what time is.

Re: Leap second causing Linux server crashes?

#57
post #32

Earlier quoted context omitted.

A lot of engineers[1] spent a lot of time successfully fixing Y2K bugs. Because nothing well known blew up, many people wrongly assumed that Y2K was never a real problem to begin with. [1] I moved a Fortune 100 manufacturing company's database off an ancient mainframe that would've been disastrous come Y2K. It went smoothly and was thus a thankless job. They paid well though (mid six figures - those were the days).

When people say mid-six figures, do they mean 500k? Or 150k?

I'd usually say just Google it, but coincidentally enough one of the front page results is someone asking the same question on this very site:

http://news.ycombinator.com/item?id=2261637

It means 500k, or there abouts; 400-600k would probably qualify, with anything higher or lower being mid to high or low to mid six figures, respectively.

Re: Leap second causing Linux server crashes?

#58

2012. and we still have problems keeping track of time. This is both fascinating and scary. P.S. for people wanting to know more this video is simple to understand but really amazing http://www.youtube.com/watch?v=xX96xng7sAE

From discussion of this same issue in prior threads, my takeaway was (a) it's really not at all difficult to handle leap seconds, but (b) the POSIX standard specifically disallows them, by specifying that a day must contain exactly 86400 seconds. (Analogously, imagine if leap days occurred as normal, but a "year" by definition contained exactly 365 days.) The existence of leap seconds means that it's not possible to…

A clever solution would be keeping an internal time and generating POSIX times (and human friendly times) as needed. This way, leap seconds will never touch true system time.

Re: Leap second causing Linux server crashes?

#59
Pardon the ignorance if this is a stupid question. I've been looking at some of my hosts and have noticed a message "Clock: inserting leap second 23:59:60 UTC" in dmesg output but each of the hosts is in the EDT timezone so the I was under the impression that the leap second hadn't been applied yet. So what does that mean? That the systems have applied the leap second successfully or have only received it from their NTP servers?

Re: Leap second causing Linux server crashes?

#60
post #32

Earlier quoted context omitted.

A lot of engineers[1] spent a lot of time successfully fixing Y2K bugs. Because nothing well known blew up, many people wrongly assumed that Y2K was never a real problem to begin with. [1] I moved a Fortune 100 manufacturing company's database off an ancient mainframe that would've been disastrous come Y2K. It went smoothly and was thus a thankless job. They paid well though (mid six figures - those were the days).

When people say mid-six figures, do they mean 500k? Or 150k?

$100/h approaches $200k, and consultants can definitely make $250/h+.
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