Re: Why do we still have 32 bit counters? Interrupt counters overflow within 50 days

From: Henrique de Moraes Holschuh
Date: Mon Oct 06 2014 - 15:35:08 EST


> > Tools expect the number of interrupt to increase linearly and not jump by
> > 2^32 once in awhile. There are functions in the kernel (/proc/stat) that

...

> I understand that, I just wonder why nobody noticed before. It's been
> that way forever :)

Any proper tool that interfaces to snmp-like counters expects and deals with
worse: sudden counter resets.

And it has been that way forever :-) So people who use such tools would
hardly notice any warp-arounds...

So, the question becomes: which tools are misbehaving? Maybe they should
adopt snmp-like counter reset detection for peak filtering, and we could
leave 32-bit alone, and increase the counter size only on for 64-bit?

--
"One disk to rule them all, One disk to find them. One disk to bring
them all and in the darkness grind them. In the Land of Redmond
where the shadows lie." -- The Silicon Valley Tarot
Henrique Holschuh
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