Brett Delmage <[EMAIL PROTECTED]> writes: > On Mon, 13 Feb 2006, Sergei Organov wrote: > > <nice analysis deleted> > >> Overall, the above analysis suggests LIFO is never better than FIFO and >> it could be much worse than FIFO. >> >> Isn't it time to finally get rid of LIFO wait queues in eCos? Any >> objections? > > Isn't ECOS about choice?
Well, unfortunately choice doesn't come for free. More testing, more opportunities for bugs, more confusion, etc. I believe useless choices are evil. > Make this configurable option and allow users to try both. :-) Which of the options do you suggest to be the default? How do you explain users the criteria to choose one algorithm or another? How will user compare the choices in his tests when most of time the algorithms behave exactly the same? How do you explain why LIFO choice is there in the first place if it has no advantages? For example, the "array" choice for DSR queue does have an excuse as being interrupts-disable-free, and it has an excuse of not being the default as it has potential problems with missing DSRs. What's an excuse for keeping LIFO choice? The only one I see is backward compatibility, but due to the fact that eCos never specified exact order of DSRs it shouldn't matter. -- Sergei. -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss
