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Leap seconds & the kernel

Leap seconds & the kernel

Posted Jul 1, 2012 20:55 UTC (Sun) by theophrastus (guest, #80847)
In reply to: Leap seconds & the kernel by Cyberax
Parent article: Kernel prepatch 3.5-rc5

I guess what i was hoping for - and thankee for any insights! - was more along the lines of: "...process_table scheduler counts up to a hardwired 86,400 and then increments day_count..." ? and/or what does Java have to do with it? (as various reports have reported)


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Leap seconds & the kernel

Posted Jul 1, 2012 21:09 UTC (Sun) by Cyberax (✭ supporter ✭, #52523) [Link]

No, it's more like "incremental seconds counter and absolute time diverge in an unexpected way".

Leap seconds & the kernel

Posted Jul 1, 2012 22:03 UTC (Sun) by alankila (subscriber, #47141) [Link]

Given that wide array of programs were affected, not just java, it was a more general issue. Apparently futexes immediately timeouted after the leap second was applied, and this caused high CPU usage.

The freakish thing was that just restarting the affected program did not fix it. I'm still waiting for the full LWN exposé of this particular issue...

Leap seconds & the kernel

Posted Jul 2, 2012 8:54 UTC (Mon) by Cyberax (✭ supporter ✭, #52523) [Link]

Looks like the problem has been identified: http://article.gmane.org/gmane.linux.kernel/1321284

Oh well, I guess I'll wait 4 more years to see if it's fixed by that time :)

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