On Fri, 06 Oct 2000, Jacob Kuntz wrote: > using a parallelized booting sequence probably won't make enough of a > difference for say, car mp3 players, to boot normally, instead of using > suspend to disk. still, it's a cool idea. as long as it can be done > gracefully. The keywords are "as long as it can be done gracefully." You need to design a new /etc/init.d/rc which instead of reading the rcS.d and rc?.d link farms, reads the paralelized boot sequence from somewhere else in /etc AND the old serialized sequence from the proper rc?.d folder, merges the two, and executes the resulting list of serialized and parellized initscripts. This needs quite a lot of work to be done right, but it is viable... as long as you have a *human made* file describing all allowed paralelizations (and everything else *especially stuff not in the allowed paralellization list* runs serialized as it would be done by the stock rcS script, when compared to each other AND the now paralelized initscripts). There is not enough information in place (in Debian) to build the paralelization list automatically. See the file-rc package for ideas. Go read the LSB initscript stuff for ideas on supplying the machine-readable data required for paralelizing stuff automagically. Actually, if you pull this design off, I guess the LSB guys might want to see it. I'd suggest writting in a piece of paper a list of all the initscripts in your system, in their current start sequence along with the time each one takes to start. Now, paralelize it in paper (and make sure not to try to run stuff in /usr before /usr is mounted, etc... you'll notice there are quite a large number of deadly traps here), and check how much time you gained in an ideal machine (two tasks running in parallel do not slow each other down -- which is not nearly close to reality, btw). Then post the data and results, and we will have a reasonable idea if it is actually worth the trouble to implement and deploy. My off-the-cuff guess is "we don't gain enough time to be worth the trouble". But I may be wrong :^P -- "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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