From 1e67a761cbfa94a69cec2f5709d23d7983cd0fc1 Mon Sep 17 00:00:00 2001 From: Thomas Schwinge Date: Thu, 25 Nov 2010 11:55:21 +0100 Subject: Talk about advantages, challenges, how many developers, why so few developers. --- .../benefits_of_a_native_hurd_implementation.mdwn | 87 ++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 open_issues/benefits_of_a_native_hurd_implementation.mdwn (limited to 'open_issues/benefits_of_a_native_hurd_implementation.mdwn') diff --git a/open_issues/benefits_of_a_native_hurd_implementation.mdwn b/open_issues/benefits_of_a_native_hurd_implementation.mdwn new file mode 100644 index 00000000..34e49e86 --- /dev/null +++ b/open_issues/benefits_of_a_native_hurd_implementation.mdwn @@ -0,0 +1,87 @@ +[[!meta copyright="Copyright © 2010 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]]."]]"""]] + +[[!tag open_issue_documentation]] + +What are the benefits of a native GNU/Hurd system, now that Linux et al. can do +so much? Think [[hurd/translator]]s: FUSE, [[hurd/subhurd]]s: User-Mode-Linux +and other virtualization techiques, and so on. + +It is possible to begin [[implementing_Hurd_on_top_of_another_system]], but... + +IRC, #hurd, August / September 2010 + + ArneBab: but Neal and I were not happy with that alone. We were + looking for deeper improvements to the system, for, I think, sound + reasons. That is what brought us to the L4/Coyotos technologies + ArneBab: as you are writing a kernel in user space, you can still + do kernel improvements there + ArneBab: if you take it very far, you end up with a kernel that + runs Linux in user space (just flip the two) for the drivers + ArneBab: that is what the L4 people did with the DDE + +([[DDE]]) + + ArneBab: so, with these different cuts, there are different + opportunities. on the one end, you can run Linux as normal and get some + of the Hurd features such as translators in some programs. At the other + end, you can do whatever you want and run some linux code for the drivers + or none at all. + ArneBab: one of the big questions then becomes: at which point + can the advantages offered by the Hurd be realized? + ArneBab: and that's not entirely clear to me + when I worked on this with Neal, we pushed further and further + into need-to-change-everything land + while the current efforts on the Hurd seem to be more equivalent + to the could-run-it-in-userspace-on-top-of-Linux camp + marcusb: for that I think we need a way to move towards them step + by step. Would it be possible to get the advantages of better resource + allocation with a Viengoos in userspace, too? + and when that is stable, just switch over? + ArneBab: I don't know. I suspect these people will know before + us: http://lxc.sourceforge.net/ + something like implementing flip points: flip Linux with Hurd to + Hund with Linux. Flip Mach with L4 to L4 with Mach. + lxc sounds interesting. + note that these efforts address security concerns more than other + concerns + so they will get isolation long before sharing is even considered + but some of the issues are the same + once you allow malware to do what it wants, it's a small step to + also allow the user to what he wants :) + it kinda looks like hacking it where it doesn’t really fit again… + there I ask myself when the point comes that doing a cleaner + design offsets the popularity + they are pushing more and more stuff into userspace + which is a good thing (to me) + it’s hard to clearly describe how, but even though I like having + more stuff in userspace, the way it is bolted onto Linux doesn’t feel + good for me. + FUSE is cool, but if I use it, I am at a disadvantage compared to + a non-fuse user + while in the Hurd, these additional options are on eqal footing. + ArneBab: are they pushing more and more into user space? I don't + think so. I see more of the reverse, actually + or maybe both + FUSE, lxd and scheduling in userspace move to userspace + well, KMS moved to the kernel + to avoid flickering when switching between X and the console? + marcusb: Do you experience FUSE lxc and such being secondclass in + Linux, too, or is that just a strange feeling of me? + marcusb: and that splits the users into those who can get stuff + into the kernel and those who can only work in userspace – which I don’t + really like. + That’s one more advantage of the Hurd: eqal footing for all + (except the Mach hackers, but they have a very limited terrain) + ArneBab: but UML kernel module is minimal, and Linus didn't have + a principled objection to it (but just wanted a more general solution) + ArneBab: as a side note, although people keep complaining, the + linux kernel seems to be growing steadily, so getting stuff into the + kernel doesn't seem too hard. 8-O -- cgit v1.2.3