On 06/15/2012 02:26 PM, Tomas Frydrych wrote: > > On 15/06/12 20:49, Tim Bird wrote: >> On 06/14/2012 11:31 PM, Tomas Frydrych wrote: >> IMHO, the whole notion of starting with a big system and >> subtracting what you don't want in order to create a minimal >> system is the wrong approach. > > At no point in this discussion was such an approach advocated by anyone.
Well, that is the logical alternative. If we suggest using sysvinit now because it's the standard, then soon we'll say that for systemd, which means I'll have to include cgroups in my kernel, etc etc. I dont think Tim's comment was wrong there. Of course "big system" is subjective, to me that's anything over 4 MB of storage and 8MB of RAM, for Tim, that's 1 MB of RAM. And for the purposes of poky-tiny, anything that adds functionality, complexity, storage or memory size, or runtime needs to be considered for the chopping block. > > >> I realize you said that with a smiley, so I'm not trying to be >> dismissive or harsh, but I do think that if you want the features >> of some other init system, then the right answer is to use them, >> and not complain about this one. > > I am not complaining, I have asked what the specific, quantifiable, > objective of creating the home grown init 'procedure' is, IMHO that is > an entirely reasonable question to an RFC, the answer to which should > inform the design. Agreed, a very valid question and one I am still working through the numbers for. We save ~3k in busybox size by using SETSID and CTTYHACK rather than the busybox INIT. This is less than 1% of the busybox binary, not a huge savings. I'll look at the rest, but it's more difficult to quantify as it is dependent on the number of sysvinit scripts used - and of course the more that are used, the more likely the image should be using sysvinit anyway. So... I'll look into this some more. > > If we are talking about targeting 1MB of RAM then it is unavoidable that > the system has to be hand crafted to a fair degree. It is not what I'd > consider the typical Poky use case, but within those constrains, I'd > probably be looking at eliminating shell scripts altogether in my > customization of whatever Poky offers. poky-tiny is looking to define a new typical use-case that differs from the poky use case (poky and poky-tiny the DISTROs of course). Perhaps you just meant Poky the project, in which case, I think the same point applies, we're trying to extend the typical use cases to include very small systems. Your point on eliminating shell scripts is a good one though. My approach here has been to make it as minimal as is practical while still having a somewhat usable system "out of the box". To me this means a shell is available, networking is supported, etc etc (see the poky distro definition for more specifics). Your main point is of course still valid: What do I get by dropping init and is it worth being different for that? I'm still looking. -- Darren Hart Intel Open Source Technology Center Yocto Project - Linux Kernel _______________________________________________ yocto mailing list yocto@yoctoproject.org https://lists.yoctoproject.org/listinfo/yocto
