From 2603401fa1f899a8ff60ec6a134d5bd511073a9d Mon Sep 17 00:00:00 2001 From: Thomas Schwinge Date: Tue, 7 Aug 2012 23:25:26 +0200 Subject: IRC. --- community/gsoc/2012/virt/discussion.mdwn | 216 +++++++++++++++++++++++++++++++ 1 file changed, 216 insertions(+) create mode 100644 community/gsoc/2012/virt/discussion.mdwn (limited to 'community/gsoc') diff --git a/community/gsoc/2012/virt/discussion.mdwn b/community/gsoc/2012/virt/discussion.mdwn new file mode 100644 index 00000000..31b9ce01 --- /dev/null +++ b/community/gsoc/2012/virt/discussion.mdwn @@ -0,0 +1,216 @@ +[[!meta copyright="Copyright © 2012 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + + +# IRC, freenode, #hurd, 2012-07-19 + + well, I really actively started last week, so I'm ironing my + various use cases and above all I'm taking my barings in Hurd's code + I'm currently reading boot/ and pfinet/ + sorry for asking but + can you describe brielfy what you mean to achieve + i know it sounds weird but the project description is a bit vague + for me + OK + the main goal is to be able to easily spawn a subhurd that's + connected in some way to its host + ok + mainly connected by network, possibly sharing resources like + FS + is it similar in spirit with something like linux containers ? + IIRC about them, yes + ok + that will do for me then + Yes, so not complete virtualization, but instaed limitied to + several components. + lxc with more runtime features to increase/decrease the level of + isolation + at first it would be static, at creation time only + ok, i clearly understand the proposal now :) + what kind of help could you need in the near future ? + (except permanent access to youpi's brain?) + Yes, that's my question, too -- what can we do to "get this + thing going". + by monday or tuesday I should be clear on what I understand + or not in the code + I'm still a bit up to my elbows in it + at that point I'll be happy to be able to pop a lot of + questions about it + so you'll be ready for the next meeting + yeah + Please do as soon as there are questions that you cannot + resolve in a reasonably short amount of time. + So often a quick hint from someone else already helps to ge + un-stuck. + OK + There is no problem with asking for help given this huge and + convoluted code-base, where often design decisions are not obvious, too. + I will + Good. :-) + nowhere_man: hm... what you said so far doesn't sound any + different than the work zhengda already did on boot years ago... + (although none of it ever got upstream IIRC :-( ) + antrik: wasn't aware of it, is there some code published? + There are bits and pieces, but certainly there is enough work + left to be done, to put it all together. + yes, his git repository should be up somewhere. it's quite + convoluted though, as he worked on several things, and also wasn't very + experienced with revision control in the beginning + nowhere_man: + http://www.gnu.org/software/hurd/community/gsoc/2008.html + nowhere_man: http://www.gnu.org/software/hurd/user/zhengda.html + Second section of the latter one. + well, my understanding of the proposal (and more or less what I + was driving at in the project idea, which is rather vague admittedly) is + something lighter than a real subhurd... rather some kind of thin + subenvironment that doesn't actually boot a complete system instance with + various daemons etc. + nowhere_man: It is certainly valid for you to use pre-existing + code/patches, by the way. + BTW, regarding the "full subhurd" thing, the missing pieces are + mostly virtual device implementations + (that and some tough bug(s) remaining in zhengda's modified + boot...) + cool, I'll take a look + in any case, getting a picture of the work zhengda did is, is + definitely the first thing to do :-) + nowhere_man: I'll also try to locate some bits and stuff from + his verious repositories (I just fond a Subverision one; will convert to + Git). + tschwinge: I'm pretty sure zhengda's git repository was converted + from the SVN one... + antrik: Thanks for reminding us about this -- I failed to + remember all that. + (which was in turn converted from CVS...) + antrik: OK, will have a lot. + Yeah, found a CVS tree, too. ;-) + BTW, zhengda's work more exactly was about subhurd without root + privileges. but that lays a lot of the groundwork for all kinds of more + flexible subhurd usage + (but it's still quite a different thing that thing + subenvironments, so don't get confused...) + err... thin subenvironments + + +# IRC, freenode, #hurd, 2012-07-27 + + bddebian: I'm actually not progressing much while reading the + source, I'm jumping all over the place to grasp the various types and + functions used where I start + would there be a few starting points that could help me? + nowhere_man: So what exactly is your status; what are you + doing, what do you need help with? We surely can provide help, but need + to know where. + I'm starting from the source of boot/ and pfinet/ and as soon + as I encounter something that I don't understand, I find its definition + I'm kind of doing a depth-first search of what I need to + understand in the source code + I'm wondering if there are a few places in the source code + that I should start reading before anything else + well, I'll have to go in a few minutes + I'll continue my DFS ;-) + + +# IRC, freenode, #hurd, 2012-08-02 + + well, I made a leap forward in understanding the code, when I + stopped my DFS + in hindsight, I'd say my way of approaching the code was + probably one of the worst possible + oh + OK, so at least you learned something, which is good. + So, what's the new approach? And what are you working on at + the moment + ? + I just remembered SICP, the idea of wishful thinking when you + code, and didn't bother with the fine details behind what I'm reading + like, I don't really get what happens when a Mach port is + allocated, but I know approximately what a Mach port is + So originally you worked on investigating all that, every line + of code? + almost, yeah + nowhereman: again, feel free to ask + Yes indeed -- that's too complex for a single person to tackle + at one time. + and quickly + don't loose time + Not even braunr and I have looked up all these things. + (Speaking for Richard here, but I'm quite sure he'll agree. Perhaps he + has in fact looked up all the Mach things, though.) + nowhereman: ufc? + BTW, last week I wanted to push my description of how the tool + could be used, the use cases + ufs + but flubber is not online + nowhereman: Oh, why ufs specifically? + don't waste time on ufs + really + nowhereman: Yes, flubber is down. But you can push directly to + the Savannah repository. + nowhereman: Please immediatelly tell us if you're stuck on + something, like flubber not being available. + We may not be able to help immediatelly, but we're the at least + aware of issues. + and we may be able to help immediately :) + As we're not sitting in a lab next to each other, we can't tell + otherwise what's going on. + We may in fact even be able to tell you immediatelly to use + Savannah instead of flubber, indeed. + nowhereman: So, back to ufs -- which you don't specifically + need to look at, I think -- ext2fs is what everyone uses. But even there + you shouldn't really need to know many details/internals. + OK, I was looking into it has it appears in hurd.boot + Ah, OK. Yeah, that's just an example/template, and should use + ext2fs nowadays. + in fact, as far as FS are concerned, I suppose I will merely + need to know how to pass a port to the host's FS to some proxy FS in the + subhurd + mmmh, Savannah only mentions a hurd.git + Exactly that is the abstraction level you need, yes. + I'm looking at http://savannah.gnu.org/git/?group=hurd + Yeah, that's a known shortcoming -- look here instead: + http://git.savannah.gnu.org/cgit/hurd + Here is some more up-to-date stuff on subhurds: + http://www.gnu.org/software/hurd/hurd/subhurd.html + nowhereman: You know how to tell git to add a new remote to + your web pages checkout and such stuff? + yeah, no problem with that + have you prepared any question to ask us ? + the only I have now is if you can tell me where to look in the + code about passing Mach ports + you don't pass ports, you pass rights + http://www.gnu.org/software/hurd/gnumach-doc/index.html is the + best location to have a look at + + http://www.gnu.org/software/hurd/gnumach-doc/Exchanging-Port-Rights.html#Exchanging-Port-Rights + i suppose the mig doc will help too, as you may be using a higher + level interface to exchange rights + be careful about user references on port rights + deallocate releases a reference, it doesn't immediately destroy a + resource + portinfo -v can help monitoring a task's rights + nowhereman: so what are you planning to do now ? + during the next week + documenting what I understand from the boot process and where + things can be changed to fit my various use cases + do you expect that to take the whole week ? + and doing some first modifications to servers for the simplest + cases + ok + well i hope you're able to really start working on it soon, and + won't face weird issues in the meantime + i'm a bit disappointed that you don't have more questions + my feeling is you either did understand everything (except passing + port rights), or you didn't attempt to seriously understand the code + or you don't dare ask questions + this is something that must change + or these meetings won't be as useful as they could be + Yes. But also please don't wait for the meetings, but ask + questions throughout the week, too. -- cgit v1.2.3