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An unexpected perf feature
LWN.net Weekly Edition for May 16, 2013
A look at the PyPy 2.0 release
PostgreSQL 9.3 beta: Federated databases and more
LWN.net Weekly Edition for May 9, 2013
The leap second bug
Posted Jul 4, 2012 10:03 UTC (Wed) by cmccabe (guest, #60281)
Having your 1 second mutex timedwait last for an hour because someone set the wall clock time back an hour, on the other hand, is not useful. Having your 1 second wait take 2 seconds because of a leap second is not useful.
Assuming that wall-clock time is properly synchronized across all nodes in a distributed system is usually not a good idea. It introduces operational complexity and more things to go wrong. And even the best maintained, properly synchronized clocks aren't usually really all that synchronized.
What we have here is a bad default, unfortunately. Most timeouts should not be in terms of wall-clock time-- ideally, none, except for calendar programs and similar.
Posted Jul 5, 2012 3:03 UTC (Thu) by dirtyepic (subscriber, #30178)
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