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A comment on One second per second is harder than it sounds. Parent comment

Re:One second per second is harder than it sounds by chubot on Tuesday July 22, 2014 @04:46AM (#8067902)
So that's exactly why you don't depend on hardware clocks -- you use software techniques when your algorithm depends on some notion of time.

The point of Lamport's paper is that time in distributed systems is a partial ordering, not a total ordering. If you are taking values from hardware clocks, you are using a total ordering.

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Re:One second per second is harder than it sounds by tlarkworthy on Tuesday July 22, 2014 @11:29AM (#8069484)
Google spanner is a DB that uses atomic clocks distributed world wide. They seem to think the pain involved dealing with partial ordering is not worth the hassle given there genuinely is a total ordering on operations.

http://en.wikipedia.org/wiki/Spanner_(database)

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Re:One second per second is harder than it sounds by dllthomas on Wednesday July 23, 2014 @01:47AM (#8073087)
"given there genuinely is a total ordering on operations."

I thought relativity says there genuinely isn't (but it's close enough we can fudge it...)

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Re:One second per second is harder than it sounds by tlarkworthy on Wednesday July 23, 2014 @07:46AM (#8073812)
ha! I think its ok as long as all parties involved are travelling on the earth and not around it near the speed of light

http://en.wikipedia.org/wiki/Relativity_of_simultaneity

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Re:One second per second is harder than it sounds by dllthomas on Wednesday July 23, 2014 @10:34AM (#8074562)
Right. Like I said, we can (presently) fudge it. When we get moving faster that ceases to be the case.
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Re:One second per second is harder than it sounds by keeperofdakeys on Tuesday July 22, 2014 @04:57AM (#8067928)
Yeah, but you can't have your clocks drifting a lot. It's fine if they are consistently wrong, but when a second isn't a second, things can start to screw up.
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Re:One second per second is harder than it sounds by judk on Tuesday July 22, 2014 @10:14AM (#8069068)
Does Lamport's design use seconds at all, or use only "happens before" statements?
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