[Spread-users] Spread rollout to lots of machines

[Steven Dake]

Matt,

Ok I see what your trying to do..  That should work if you keep the
number of daemons to less then 128...

I am not certain about performance penalties you may find for having
members not active in the membership..  Atleast there will be no
pretransmission or posttransmission delay, however, there may be some
extra minor processing required.  The impact is probably minimal and I
doubt you would notice much change in delivery latencies or bandwidth
available.


On Mon, 2004-02-02 at 10:41, Matt Sergeant wrote:
> On Mon, 2 Feb 2004, Steven Dake wrote:
> 
> > Matt,
> >
> > Spread supports 128 nodes max.  I suspect if you deploy all of them in
> > one segment, your going to have serious performance problems (ring
> > rotation takes alot of time).  According to the maintainers, spread has
> > been tested with 50-60 nodes at one time.
> 
> That's definitely not the intention. I want one segment per "rack" (we
> call them "towers", but it's basically a 19" rack full of servers).
> 
> The solution I've come up with is this RPM post install script:
> 
> %post
> if ! grep -q '# Tower' /etc/spread.conf; then
> perl -e '$data = qx(/sbin/ifconfig eth0 | grep "inet addr");
> ($ip, $bcast) = $data =~ /inet
> addr:\s*(\d+\.\d+\.\d+\.\d+)\s+Bcast:\s*(\d+\.\d+\.\d+\.\d+)/i;
> ($rhs, $tower, $server) = $ip =~ /^(\d+\.\d+)\.(\d+)\.(\d+)$/;
> @range = ($server < 128) ? (1..127) : (128..254);
> print "# Tower $tower\nSpread_Segment $bcast:4803 {\n";
> print "\tserver-$_  $rhs.$tower.$_\n" foreach (@range);
> print "}\n\n";' >> /etc/spread.conf
> fi
> 
> It looks a bit hacky, but I think it'll work just fine.
> 
> Is there a performance penalty for including clients that won't ever join
> the group?
> 
> Matt.