[Ns-developers] log time -> log context

[Mathieu Lacage]

On Sun, 2008-05-18 at 15:10 +0100, Gustavo Carneiro wrote:
> On 17/05/2008, Gustavo Carneiro <gjcarneiro at gmail.com> wrote:
> >
> > I am unhappy about current logging.  As I reported some weeks ago, I miss
> > the node number in logging messages, among other things.
> >
> > The repository gjc/ns-3-log-context I am (slowly) uploading tries to
> > provide that.  First it renames LogTimePrinter to LogContextPrinter and so
> > on.  Then  it adds Simulator::SetCurrentNode (int32_t nodeId) method (and
> > some other related methods).  This method is to be called when the
> > simulation is changing current node, for some reason.  The most common
> > reason is a NetDevice receiving a packet.  Also EvenImpl receives a new
> > nodeId attribute (32 bits), so that when a node "schedules" an event, when
> > the event is actually run Simulator::SetCurrentNode is called with that
> > nodeId.
> >
> > This patch is barely tested, so be warned.  It doesn't seem to work 100%;
> > I'll have to figure out why later.
> 
> 
> OK, problem was that user code was calling UDP socket API methods.
> Naturally, with API calls from user code NS-3 does not _know_ the current
> context.  A few lines of code added to udp-socket.cc took care of it.

I would have expected that you modify the code of applications to set
the node id prior to scheduling socket-related events. Actually, you
might get away with just modifying Application::Start and Stop

> 
> The output is now looking like this:
> [...]
> [4479922400ns node 0013] Ipv4L3Protocol:Receive(0x649770, 0x7fff2d57e700,
> 0x6f58b0, 2048, 03-06-00:00:00:00:00:0d)
> [4479922400ns node 0013] Ipv4L3Protocol:Receive(): Packet from
> 03-06-00:00:00:00:00:0d received on node 13
> [4479922400ns node 0013] Ipv4L3Protocol:Forwarding(1, 0x6f58b0,
> 0x7fff2d57e560, 0x6481e0)
> [4479922400ns node 0013] Ipv4L3Protocol:Forwarding(): Forwarding logic for
> node: 13
> [4479922400ns node 0013] Ipv4L3Protocol:Forwarding(): For me (destination
> match)
> [4479922400ns node 0013] Ipv4L3Protocol:ForwardUp(0x649770, 0x6f58b0,
> 0x7fff2d57e560)
> [4479922400ns node 0013] UdpSocket:ForwardUp(0x6f6db0, 0x6f3ec0, 172.16.0.3,
> 49153)
> [4481250000ns node 0011] UdpSocket:Send(0x6f3640, 0x6ec8b0)
> [4481250000ns node 0011] UdpSocket:DoSend()
> [4481250000ns node 0011] UdpSocket:DoSendTo(0x6f3640, 0x6ec8b0, 172.16.0.5,
> 9)
> [4481250000ns node 0011] Ipv4L3Protocol:GetIfIndexForDestination(0x648dd0,
> 172.16.0.5, 0x7fff2d57eb0c)
> [4481250000ns node 0011] Ipv4L3Protocol:GetIfIndexForDestination():
> Requesting Source Address
> [4481250000ns node 0011] Ipv4L3Protocol:GetIfIndexForDestination(): Found
> ifIndex 1
> [4481250000ns node 0011] UdpSocket:DoSendTo(): Route exists
> [4481250000ns node 0011] Ipv4L3Protocol:GetAddress(0x648dd0, 1)
> [4481250000ns node 0011] Ipv4L3Protocol:GetInterface(0x648dd0, 1)
> [4481250000ns node 0011] Ipv4L3Protocol:Send(0x648dd0, 0x6fb2a0, 172.16.0.3,
> 172.16.0.5, )
> [4481250000ns node 0011] Ipv4L3Protocol:Lookup(0x648dd0, 0x7fff2d57e870,
> 0x6fb2a0, 0x7fff2d57e8c0)
> [4481250000ns node 0011] Ipv4L3Protocol:Lookup(0x648dd0, 4294967295,
> 0x7fff2d57e870, 0x6fb2a0, 0x7fff2d57e7f0)
> [4481250000ns node 0011] Ipv4L3Protocol:Lookup(): Requesting route
> [4481250000ns node 0011] Ipv4L3Protocol:SendRealOut(0x648dd0, 1, 0x649e30,
> 0x6fb2a0, 0x7fff2d57e870)
> [4481250000ns node 0011] Ipv4L3Protocol:SendRealOut(): Send via interface 1
> [4481250000ns node 0011] Ipv4L3Protocol:GetInterface(0x648dd0, 1)
> [4481250000ns node 0011] Ipv4L3Protocol:SendRealOut(): Send to destination
> 172.16.0.5
> [4483672400ns node 0013] Ipv4L3Protocol:Receive(0x649770, 0x7fff2d57e700,
> 0x6f7cc0, 2048, 03-06-00:00:00:00:00:0d)
> [4483672400ns node 0013] Ipv4L3Protocol:Receive(): Packet from
> 03-06-00:00:00:00:00:0d received on node 13
> [4483672400ns node 0013] Ipv4L3Protocol:Forwarding(1, 0x6f7cc0,
> 0x7fff2d57e560, 0x6481e0)
> [4483672400ns node 0013] Ipv4L3Protocol:Forwarding(): Forwarding logic for
> node: 13
> [4483672400ns node 0013] Ipv4L3Protocol:Forwarding(): For me (destination
> match)
> [4483672400ns node 0013] Ipv4L3Protocol:ForwardUp(0x649770, 0x6f7cc0,
> 0x7fff2d57e560)
> [4483672400ns node 0013] UdpSocket:ForwardUp(0x6f6db0, 0x6f5fd0, 172.16.0.3,
> 49153)
> [...]
> 
> It's very easy to filter for specifc node ids using grep.
>