Re: : Re: : No systemd discussion?

On Mon, Aug 18, 2014 at 07:11:34AM +0000, Peter wrote:
> Let's be honest (warning: I am into VERY small systems which probably have
> no room for systemd - but see below):
> 
> The scripts are not the problem. The problem is the daemons and other things
> they start/stop, which can be programmed in ways which make them
> nonresponsive for a variety of reasons. init(1) has a sane way to cope with
> runaway processes, by making them sleep for a bit if they go insane. Zombies
> should be dealt with by process group mechanisms which exist, but are not
> used by anyone. It is really easy to write a bit of code which registers
> "children to be killed in case of process group leader demise" perhaps
> directly into /var/run/thedaemon.pid files, to be used by a slightly modded
> init(1) when a process dies or runs away.
> 
> Adding systemd is not going to change that. A daemon that dies repeatedly
> very quickly will have to be "quarantined" for a while. systemd will not fix
> the underlying problem, which is certain daemons are not high quality and
> robust. Using systemd to "fix" them is, imho, barking up the wrong tree.
> 
> What systemd *could* have done, is to replace the need for sh(1) and init(1)
> in small systems assuming it would have some sort of shell or smnp interface
> for control from a shell-less terminal, serial line, or network connection.
> It would also have to be rather good at doing system things to replace sh
> and init in size, so sh(1) would not be needed at all, as those 2 together
> are fairly small (assuming ash or another startup sh compatible shell is
> used), and do a LOT of things besides running sysv init scripts.
> 
> The way it is now, I see systemd as an unneeded complication which will
> break many many things before starting to work "right" for most people. And
> by most people I explicitly exclude "ready made" distribution users a la
> ubuntu etc., who are end users, and, who, by their own (!) definition,
> should do nothing more than push buttons and be rewarded with actions,
> reagrdless how those actions are achieved.
> 
> Let's say I will be interested in systemd on small systems *after* openwrt
> and other embedded distributions adopt it *and* the inevitable anguished
> help cries on relevant forums die down a bit. That could take a year or two
> after they start using it, judging by how things went in the past. I so wish
> I am wrong about the time-frame.
> 
> Until then, I see systemd based kernels as a fork... harsh, but a serious
> problem for people who need to tinker under the hood frequently, as I have to.

I didn't say systemd was a good solution, I just said the scripts
are crap.

I would love to see a good solution.  I saw a comment from Rob Landley
about creating a small version of launchd (which I think he intends to
name lunchd) as part of his toybox package.  He has quite the rant about
systemd here: https://forums.darknedgy.net/viewtopic.php?id=3844

And yes for small systems systemd is not an option.  I currently don't
expect to ever use systemd on the routers we make at work.  They are
probably nowhere near as small as what you are dealing with though.

-- 
Len Sorensen
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