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Somewhat related, the classic "Respite from the OOM killer" by Andries Brouwer: An aircraft company discovered that it was cheaper to fly its planes with less
by willvarfar 12y ago
Somewhat related, the classic "Respite from the OOM killer" by Andries Brouwer:
An aircraft company discovered that it was cheaper to fly its planes with less fuel on board. The planes would be lighter and use less fuel and money was saved. On rare occasions however the amount of fuel was insufficient, and the plane would crash. This problem was solved by the engineers of the company by the development of a special OOF (out-of-fuel) mechanism. In emergency cases a passenger was selected and thrown out of the plane. (When necessary, the procedure was repeated.) A large body of theory was developed and many publications were devoted to the problem of properly selecting the victim to be ejected. Should the victim be chosen at random? Or should one choose the heaviest person? Or the oldest? Should passengers pay in order not to be ejected, so that the victim would be the poorest on board? And if for example the heaviest person was chosen, should there be a special exception in case that was the pilot? Should first class passengers be exempted? Now that the OOF mechanism existed, it would be activated every now and then, and eject passengers even when there was no fuel shortage. The engineers are still studying precisely how this malfunction is caused.
http://lwn.net/Articles/104179/ http://lwn.net/Articles/104179/
- goodwilly 12y agoGot a chuckle out of me, but if you equate processes to human lives you get an infinite amount of absurdity anyway, making this a rather meaningless analogy.
- willvarfar 12y agoDo you think that as Linux gets used in medical, military and home contexts perhaps lives may really be at risk?
- stingraycharles 12y agoThen you enter the realm about hardened / realtime systems, where guarantees about eg. execution time are required. Those usually require a different aproach to kernel development anyway -- I do know there is something like RT Linux, but I have no idea how big it is.
- justincormack 12y agoReal time Linux is lacking funding, and is not being developed much any more [1] [1] https://lwn.net/Articles/617140/ https://lwn.net/Articles/617140/
- TickleSteve 12y agoAlthough there are versions of Linux that are hard-realtime, the approach they take is to have a proper RTOS "underneath" Linux and effectively run Linux as a non realtime process. Linux as a whole is far too large and dynamic for deterministic response. Linux does get used a lot for soft realtime applications tho, especially in the military world.
- xorcist 12y agoNot necessarily. Most systems within the medical context does not have any realtime requirements, after all. A watchdog restart may be only a nuisance. It would be nice of embedded systems engineers thought about things such as memory overcommit, but in real life they are as most of us: Stuck with old code bases that someone built right before leaving.
- drzaiusapelord 12y agoYou probably wouldn't, and shouldn't, use Linux for RTOS duties. This is why we see Linux overwhelmingly on mobile phones, servers, etc and not powering your pacemaker, spacecraft, or nuclear plant. NASA uses VxWorks for a reason. http://en.wikipedia.org/wiki/Comparison_of_embedded_computer_systems_on_board_the_Mars_rovers#Performance_comparisons http://en.wikipedia.org/wiki/Comparison_of_embedded_computer...
- sp332 12y agoIt's called hyperbole. The point isn't that processes are like human lives, it's to point out that killing processes is the wrong strategy.
- deleted 12y ago[deleted]