[DNG] Technical overview of init systems
Using this 'resource' will do a disservice to Devuan. Anyone serious enough to read it will get the wrong impression that Devuan is some 'amateur' distribution not worthy of wasting professional hours on it. Scientific and technical text must at all costs avoid opinionated writing but this resource does the opposite. As said earlier, there is no objective comparism between the different inits. -- If you can't explain it simply, you don't understand it well enough. (Albert Einstein) If you cannot make abstructions about details you do not understand the concepts underlying them. ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Technical overview of init systems
On Tue, 08 Aug 2017, Martin Steigerwald wrote: > Adam Borowski - 08.08.17, 18:57: > > On Tue, Aug 08, 2017 at 11:53:56AM -0400, Steve Litt wrote: > > > Be careful recommending cgroups. > > > > > > I've never used them, and know little about them, but I know they were > > > one of the main excuses for systemd. > > > > Uhm, what? Systemd uses ELF objects too, should we go with a.out for this > > reason? > > > > cgroups are a way to say "this group of processes may not use more than 2GB > > memory". How else would you ensure a misbehaving set of daemons / container > > /etc does not bring down the rest of the system with it? > > I agree that cgroups can be a useful feature. Yet… also a bit clumsy to use, > and not free of race conditions. That written, kernel developers are working > to fix part of the clumsyness and completely and all of the race conditions > by > unifying all cgroup controllers (memory, cpu and so on) in one directory tree. is the sourcecode of systemd the *only* example implementation of an INIT 1 daemon using cgroups right now? here I see a lot of Go code https://github.com/search?utf8=%E2%9C%93&q=cgroups&type= so why systemd is considered to be the only supervisor implementation supporting cgroups? because all the rest are just libraries? I'm a bit confused and very curious ciao! ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Just out of curiosity, I wondered,
El 08/08/17 a les 23:28, zap ha escrit: > how do you enable internet in a virtual machine with qemu? > > I wanted to try to see how effectively certain distros such as gnuinos > and vuu-do work through qemu with upgrading actually working... > > ___ > Dng mailing list > Dng@lists.dyne.org > https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng > I recommend you: $ qemu-system-x86_64 -cpu host -enable-kvm -m 1024 -net nic,model=rtl8139,vlan=0 -net user,vlan=0 -cdrom devuan_jessie_1.0.0_amd64_desktop-live.iso ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Technical overview of init systems
El 09/08/17 a les 09:13, Edward Bartolo ha escrit: > Using this 'resource' will do a disservice to Devuan. Anyone serious > enough to read it will get the wrong impression that Devuan is some > 'amateur' distribution not worthy of wasting professional hours on it. > Scientific and technical text must at all costs avoid opinionated > writing but this resource does the opposite. As said earlier, there is > no objective comparism between the different inits. > If reaching perfection is a requirement, important things will not be reached. Imagine Devuan 1.0 without still being released because of Gnome lack. ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Just out of curiosity, I wondered,
Adam Borowski wrote: > My personal favourite is bridged mode, which has only an one-time setup > cost, and makes guest VMs operate exactly same as if they were physically > separate machines plugged into your ethernet switch next to the host. > As a bonus, that setup cost is shared with lxc, which is also happy in > such a bridged configuration. And also the default for Xen, which as you say "just works". It's also REALLY easy to have multiple bridges for multiple networks. AIUI you can also use Open Vswitch and have VLAN support etc to the guests, but it's not something I've ever used. ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Just out of curiosity, I wondered,
On Wed, Aug 09, 2017 at 10:13:03AM +0200, Narcis Garcia wrote: > $ qemu-system-x86_64 -cpu host -enable-kvm -m 1024 -net > nic,model=rtl8139,vlan=0 -net user,vlan=0 -cdrom > devuan_jessie_1.0.0_amd64_desktop-live.iso rtl8139 is a 100Mbit card, you really don't want your virtual network speed hobbled by emulating such gear. -- ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢰⠒⠀⣿⡁ James Damore is a hero. Even mild criticism of bigots these days ⢿⡄⠘⠷⠚⠋⠀ comes at great personal risk. ⠈⠳⣄ ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Just out of curiosity, I wondered,
On Wed, 2017-08-09 at 10:13 +0200, Narcis Garcia wrote: > El 08/08/17 a les 23:28, zap ha escrit: > > how do you enable internet in a virtual machine with qemu? > > > > I wanted to try to see how effectively certain distros such as gnuinos > > and vuu-do work through qemu with upgrading actually working... > I recommend you: > $ qemu-system-x86_64 -cpu host -enable-kvm -m 1024 -net > nic,model=rtl8139,vlan=0 -net user,vlan=0 -cdrom > devuan_jessie_1.0.0_amd64_desktop-live.iso Or you can use port forwarding: qemu-system-x86_64 -cpu host -enable-kvm -m 1024 -net nic,model=e1000 -net user,hostfwd=tcp::5556-:22 ... ssh -p 5556 localhost/ ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Just out of curiosity, I wondered,
I prefer using a VDE setup, since that lets me run qemu as user (i.e. not root), and it's easy to link up VM's across hosts with "virtual cables" over ssh. My qemu parameters are like this: -net nic,macaddr=02:aa:bb:cc:dd:02 -net vde,sock=/tmp/vde.ctl On the host, I have a vde_switch for /tmp/vde.ctl to a tap, owned by the user. Plus of course routing and such; the tap set up needs to be done as root. You can probably run a user qemo directly to a tap, but then you'll need separate taps for each VM. The VDE (vde2) method performs quite well, and lets me have several VM's through the same tap. Ralph. zap wrote on 09/08/17 07:28: how do you enable internet in a virtual machine with qemu? I wanted to try to see how effectively certain distros such as gnuinos and vuu-do work through qemu with upgrading actually working... ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
[DNG] qemu networking: Was Re: Just out of curiosity, I wondered,
On Wed, 2017-08-09 at 22:45 +1000, Ralph Ronnquist wrote: > I prefer using a VDE setup, since that lets me run qemu as user (i.e. > not root) With -net nic -net user,hostfwd=tcp::5556-:22 you don't have to run anything as root as long as the forwarded port is higher than 1024. Additionally for a second VM you can use a different port e.g. hostfwd=tcp::5557-:22 etc. On one of my hosts I run 4 VMs, on another 5. All works fine, just make sure you have enough RAM for all guests. ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Technical overview of init systems
On Wed, 9 Aug 2017 10:16:46 +0200 Narcis Garcia wrote: > El 09/08/17 a les 09:13, Edward Bartolo ha escrit: > > Using this 'resource' will do a disservice to Devuan. Anyone serious > > enough to read it will get the wrong impression that Devuan is some > > 'amateur' distribution not worthy of wasting professional hours on > > it. Scientific and technical text must at all costs avoid > > opinionated writing but this resource does the opposite. As said > > earlier, there is no objective comparism between the different > > inits. > > If reaching perfection is a requirement, important things will not be > reached. > Imagine Devuan 1.0 without still being released because of Gnome lack. I agree with you and Edward, and furthermore refuse to see connection between PID1 and the cgroups feature as something necessarily desireable. It's not like before systemd, I felt there was something wrong with any of my systems that could have been fixed by such a connection. As Edward and Narcis both say, perfection can't be reached. I take one step farther, and say that not only is a PID1/cgroups connection not perfection, but its utility is helpful only in edge cases. And I agree with Edward that the mere discussion of cgroups bends the discussion in a systemd kind of way, because it's always discussed as a necessity or at least a good thing. Cgroups is for restricting/monitoring resources for groups of processes. Very necessary for Google and perhaps for containers, but not for PID1s. It's been at least 10 years since an out of control resource-hog process locked me out of my computer in such a way I was forced to reboot, and I've never used systemd. On a dare I once ran a C no output, no sleep forever loop at nice -19, and I was still able to step in and take control. The way things are today, the mere discussion of cgroups as a desireable thing in an init horribly distorts the situation. Like Edward and Narcis said. SteveT Steve Litt July 2017 featured book: Quit Joblessness: Start Your Own Business http://www.troubleshooters.com/startbiz ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Technical overview of init systems
Edward, I think that any articles that interest people in exploring this part of their Linux systems can only be good. Edward Bartolo wrote: > Using this 'resource' will do a disservice to Devuan. Anyone serious > enough to read it will get the wrong impression that Devuan is some > 'amateur' distribution not worthy of wasting professional hours on it. > Scientific and technical text must at all costs avoid opinionated > writing but this resource does the opposite. As said earlier, there is > no objective comparism between the different inits. > -- > If you can't explain it simply, you don't understand it well enough. > (Albert Einstein) > If you cannot make abstructions about details you do not understand > the concepts underlying them. > ___ > Dng mailing list > Dng@lists.dyne.org > https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng -- Joel Roth ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] qemu networking: Was Re: Just out of curiosity, I wondered,
Svante Signell wrote on 10/08/17 00:16: On Wed, 2017-08-09 at 22:45 +1000, Ralph Ronnquist wrote: I prefer using a VDE setup, since that lets me run qemu as user (i.e. not root) With -net nic -net user,hostfwd=tcp::5556-:22 you don't have to run anything as root as long as the forwarded port is higher than 1024. Additionally for a second VM you can use a different port e.g. hostfwd=tcp::5557-:22 etc. On one of my hosts I run 4 VMs, on another 5. All works fine, just make sure you have enough RAM for all guests. Yes, that "no host setup" approach is a good one for many use cases. I'm not comfortable with the "user mode" networking, though; esp. it didn't perform well when I tried it. It's also a little troublesome when I move the (laptop) host between cable and wireless. And it brought me a couple of other opinionated thoughts when I tried it, so nowadays I always bring up a vde_switch (and a dns_masq for dhcp service) whether I run any VM or not :-) Ralph. ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Technical overview of init systems
Le 09/08/2017 à 22:46, Joel Roth a écrit : Edward, I think that any articles that interest people in exploring this part of their Linux systems can only be good. Edward Bartolo wrote: Using this 'resource' will do a disservice to Devuan. Anyone serious enough to read it will get the wrong impression that Devuan is some 'amateur' distribution not worthy of wasting professional hours on it. Scientific and technical text must at all costs avoid opinionated writing but this resource does the opposite. As said earlier, there is no objective comparism between the different inits. Despite what the author claims, this series of pages isn't about init. It is mostly about supervision and a little about containers. It assumes both are usefull, with no argumentation to motivate supervision. Confusion about init, supervision, and containers typically suggests that the author has been contaminated by systemd propaganda. Also I don't like the style of this series of explanations; there is little content within a lot of decoration and structure. Clearly the author has tried all these supervisors but his explanations could be more detailed. Didier ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Just out of curiosity, I wondered,
Adam Borowski wrote: > rtl8139 is a 100Mbit card, you really don't want your virtual network speed > hobbled by emulating such gear. It doesn't work like that. The nominal speed of the card is merely that of the real card being emulated - in the emulated version, there's no serial pipe to get the bits through (just in-memory copies/moves) and the actual throughput will be whatever the chain of bits can push through it. That's certainly the case with Xen which (AIUI) uses Qemu for the I/O stuff. Having said that, people bitten by "cr*p hardware or drivers" tend to have long memories - Realtek is a make I prefer to avoid. Now, Intel e1000 is a different matter. Yeah, I know - the newer stuff is OK, and it's only emulated not real hardware, but memories of pain are memories of pain. ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
