[OSM-dev] osm2pgsql deltas

[Steve Hill]

On Wed, 20 Jan 2010, Brett Henderson wrote:

> Matt's suggestion of running under strace might be the way to go here.  I've
> never seen anything like this before.

Got it!

For some reason, one of the threads creates a PF_INET6 socket on an 
ephemeral port, listenning on all network interfaces.  The same thread 
then creates a connection to that socket.  Due to a misconfiguration on my 
server, ip6tables was set to drop looped back IPv6 traffic, so it was 
sitting there waiting for the connection to time out.

Fixing the ip6tables config to allow looped bak IPv6 traffic has resolved 
the problem.

Some odd notes:

1. This connection can't be especially important since it was able to 
carry on working just fine without the connection present.
2. Since it is on an ephemeral port, the socket is presumably only be used 
for internal communication between threads - as such, using a socket that 
is listenning for connections on all network interfaces seems like a 
really bad idea.  This sort of stuff should be done with unix domain 
sockets, not public network sockets.
3. Of course, I have no idea if Osmosis or the JVM itself is responsible 
for this. :)

-- 

  - Steve
    xmpp:steve at nexusuk.org   sip:steve at nexusuk.org   http://www.nexusuk.org/

      Servatis a periculum, servatis a maleficum - Whisper, Evanescence