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On Mon, 17 Feb 2014 18:35:34 -0600 |
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Canek Peláez Valdés <caneko@×××××.com> wrote: |
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|
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> On Mon, Feb 17, 2014 at 11:52 AM, Andrew Savchenko |
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> <bircoph@×××××.com> wrote: |
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> > On Sun, 16 Feb 2014 15:16:36 -0600 Canek Peláez Valdés wrote: |
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> >> On Sun, Feb 16, 2014 at 2:58 PM, Volker Armin Hemmann |
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> >> <volkerarmin@××××××××××.com> wrote: |
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> >> > Am 16.02.2014 21:08, schrieb Canek Peláez Valdés: |
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> >> >> On Sun, Feb 16, 2014 at 12:59 PM, Volker Armin Hemmann |
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> >> >> <volkerarmin@××××××××××.com> wrote: |
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> >> >> [ snip ] |
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> >> >>> or it is an idiotic decision. Because features means |
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> >> >>> complexity. |
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> >> >> Yeah, like the kernel. |
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> >> >> |
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> >> >>> Complexity means bugs. |
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> >> >> Bugs get reported, bugs get fixes. Life goes on. |
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> >> |
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> >> You didn't answered this, did you? |
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> > |
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> > Bugs are different. |
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> |
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> Bugs are bugs, period. And they get reported and fixed. |
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> |
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> > Bugs in the critical system components are |
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> > critical to the whole system. |
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> |
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> Yeah, that's why we have unit testing and QA teams and stable and |
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> unstable releases, etc. |
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> |
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> > If Libreoffice or browser |
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> > segfaults, some data may be lost and inconvenience created, but the |
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> > system will continue to run. If PID 1 segfaults — everything is |
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> > lost, you have a kernel panic. |
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> |
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> And the world will end? The same happens if the kernel has an error. |
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> |
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> > That's why critical components should |
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> > be as simple and clean as possible. |
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> |
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> Like the kernel? You call that "simple"? |
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> |
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> I'm sorry, but you are (IMO) wrong: critical components should be |
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> thoroughly tested and debugged, and have integrated unit testing, and |
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> a large enough group of volunteers to test new releases before they go |
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> into the general public. |
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|
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How can you be sure if something is "large enough" if, as you say below, |
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you do not care about probabilities? |
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|
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> > SysVinit code size is about 10 000 lines of code, OpenRC contains |
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> > about 13 000 lines, systemd — about 200 000 lines. |
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> |
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> If you take into account the thousands of shell code that SysV and |
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> OpenRC need to fill the functionality of systemd, they use even more. |
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> |
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> Also, again, systemd have a lot of little binaries, many of them |
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> optional. The LOC of PID 1 is actually closer to SysV (although still |
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> bigger). |
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> |
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> > Even assuming |
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> > systemd code is as mature as sysvinit or openrc (though I doubt |
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> > this) you can calculate probabilities of segfaults yourself easily. |
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> |
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> I don't care about probabilities; |
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|
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If you do not care (= do not now anything) about probabilities |
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(and mathematics, in general), you just unable to understand |
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that debugging a program with 200K lines of code take |
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|
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200000!/(10000!)^20 |
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|
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more time than debugging of 20 different programs with 10K lines of |
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code. You can try to calculate that number yourself but I quite sure |
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that if the latter can take, say, 20 days, the former can take |
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millions of years. |
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|
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It is all the probability! Or, to be more precise, combinatorics. |
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|
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> I care about facts: FACT, I've been using systemd since 2010, |
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> in several machines, and I haven't had a single segfault. |
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|
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Have you ever tried forex? If yes, you should have been warned |
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that "no past performance guarantee the future one." |
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|
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And if you do not believe that (and do not care about probability |
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and all the stuff like that), you should visit any of the forex forums |
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where you will be suggested a magical money winning strategy that, in |
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the past, behaved very well and earned 200 or even 500% a month. |
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|
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> FACT: almost no bug report in systemd involves a |
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> segfault in PID 1. |
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> |
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> >> >> All of them are different tools providing one capability to |
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> >> >> systemd as a whole. So systemd is a collection of tools, where |
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> >> >> each one does one thing, and it does it well. |
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> >> >> |
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> >> >> By your definition, systemd perfectly follows "the unix way". |
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> >> >> |
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> >> > |
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> >> > no, it isn't. |
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> >> > |
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> >> > How are those binaries talk to each other? |
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> >> |
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> >> dbus, which is about to be integrated into the kernel with kdbus. |
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> > |
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> > And this is a very, very bad idea. Looks like you don't know matter |
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> > at all: to begin with kdbus protocol is NOT compatible dbus and |
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> > special converter daemon will be needed to enable dbus to talk to |
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> > kdbus. |
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> |
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> kdbus uses a different wire protocol than dbus; but for clients that |
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> doesn't matter; libsystemd-dbus will offer a compatibility layer (talk |
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> about "standard" and "replaceable"), so if your application uses dbus |
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> today, it will work with kdbus. |
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> |
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> Of course, new applications will take advantage of the new features |
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> of kdbus. |
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> |
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> > The |
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> > whole kdbus technology is very questionable itself (and was |
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> > forcefully pushed by RH devs), |
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> |
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> Sorry, but it's you who doesn't know the matter at hand: kdbus was |
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> (and is) written by Greg Kroah-Hartman, Linus' right hand, and who |
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> works for the Linux Foundation. |
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|
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Lol, he seems to start to use the arguments like "You even do not know |
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my elder brother/acquaintance from the street nearby who can easily |
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hit you down!" |
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|
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So, here, I would like to thank everybody in this discussion who |
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helped me to understand the danger of systemd and note that it is |
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now became pointless to continue this discussion with this "unpayed |
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systemd promoter." |
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|
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> > anyway it is possible to disable this |
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> > stuff in kernel and guess what will be done on my systems. |
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> |
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> Good for you. Guess what will be done in mine? |
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> |
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> >> > Looks broken. Broken by design. The worst form of broken. |
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> >> |
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> >> By your opinion, not others. |
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> > |
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> > That is not just an opinion. There is a science and experience |
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> > behind system's design. |
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> |
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> Yeah, what do you think about Greg Kroah-Hartman, Linus' right hand, |
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> or Keith Packard of X.org fame? None of them works for Red Hat; both |
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> of them know more about Unix and Linux than you and me together, and |
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> both of them promote systemd. |
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|
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Aha! How could you even doubt my understanding the words of these prophets! :-) |
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> I mean, I myself know a thing or two about computing and Linux, and I |
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> promote systemd (and nobody pays me, BTW), but obviously you don't |
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> need to believe in my credentials. |
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I have said you, he is just an unpayed fanatic systemd promoter! |
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|
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> And, no offense, but I will always give more weight to the words of |
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> Greg Kroah-Hartman or Keith Packard (to name only two), instead of a |
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> random user in gentoo-user. |
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> |
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> There are knowledgeable people who are against systemd. But usually |
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> they don't give *technical* sound reasons. |
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> |
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> > And all that science was ignored during systemd |
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> > architecture process if there was any at all. |
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> |
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> You should read systemd-devel and Lennart's blog posts |
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|
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And A Holy Words of our Mighty God! |
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|
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> before saying something like that. I did. |
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> |
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> Regards |