[systemd-devel] [PATCH 4/4] core: lazy distribute for Distribute pools

[Zbigniew Jędrzejewski-Szmek]

On Sun, Nov 17, 2013 at 08:46:46PM +0100, Lennart Poettering wrote:
> On Sat, 16.11.13 13:18, Shawn Landden (shawn at churchofgit.com) wrote:
> >                          <varlistentry>
> > +                                <term><varname>LazyDistribute=</varname></term>
> > +                                <listitem><para>Takes an boolean
> > +                                value. If true, Distribute=n workers will not be spawned
> > +                                simultameously, but one at a time while connections come it
> > +                                until n are running. Because of the nature of SO_REUSEPORT workers are
> > +                                spawned at an exponentially decreasing rate to the number of incoming connections.</para></listitem>
> > +                        </varlistentry>
> > +
> > +                        <varlistentry>
> 
> Hmm, so I think support for SO_REUSEPORT should just be a special case
> of the Distribute= logic. i.e. When Distribute= is set but ReusePort is
> off, then we'd pass the same original listening socket to all services
> we spawn. If Distribute is set but ReusePort is on then we'd create a
> new socket when we want to spawn a new instance, and simply bind it to
> the same sockaddr as the original one.
> 
> Thinking about this: I have the suspicion that LazyDistribute shouldn't
> be an option but the normal and only behaviour...
Agreed.

Also, I think ReusePort=1 should be the default if Distribute is used,
and the kernel supports it. I don't think there are any downsides.

Zbyszek