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Re: upstart: please update to latest upstream version

OoO  En  cette nuit  nuageuse  du mercredi  07  mars  2012, vers  00:21,
Fernando Lemos <fernandotcl@gmail.com> disait :

>> To give one particular example: systemd uses Linux-specific features to
>> accurately track all the processes started by a service, which allows
>> accurate monitoring and shutdown of processes which could otherwise
>> disassociate themselves from their parent processes via the usual
>> daemonizing trick.  POSIX doesn't provide features that allow this in
>> general, but Linux does.  (Quite possibly other OSes provide those
>> features too, but not in a standardized way.)

> By the way, upstart uses ptrace for this:

> http://netsplit.com/2007/12/07/how-to-and-why-supervise-forking-processes/

> It's an interesting trick, and probably more portable too.

Maybe we could  have an intermediate goal to patch any  daemon to add an
option  to not  fork on  start.  If  any daemon  can be  started without
forking, it seems  easy to start/stop them without  cgroups.  This would
allow to generate a sysvinit  script from systemd service description. I
don't  know  any daemon  that  does  not have  a  flag  to  not fork  on
start. The number of daemons to patch may be low.

This will not be  as clean as using cgroups, but it  won't be worst than
the actual situation.
Vincent Bernat ☯ http://vincent.bernat.im

printk("Entering UltraSMPenguin Mode...\n");
	2.2.16 /usr/src/linux/arch/sparc64/kernel/smp.c

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