Sunday 8 July 2012

Excuse me?

I dont know if people are familiar with the comedy sketch
by the "Two Ronnies", but theres a very funny item where, in a TV
Quiz, the topic chosen by the contestant is to answer the question
before last.

http://www.youtube.com/watch?v=y0C59pI_ypQ

So, I am adding TCP provider probes, and this is what happens on
a connection (to an unopen port on the destination host):


$ build/dtrace -n tcp:::
dtrace: description 'tcp:::' matched 4 probes
CPU ID FUNCTION:NAME
1 54 :connect-refused
1 51 :state-change
2 51 :state-change
2 53 :connect-request


The connection is refused, and a little while later, we make the connection
attempt. Something very strange is going on. Note that this happens on
different CPUs, so its possible that there is an ordering problem between
the CPUs, but that shouldnt normally happen.

Definitely some form of timing issue. If I connect to a remote or
non-existant host, then it looks much "saner".

Post created by CRiSP v11.0.10a-b6436


No comments:

Post a Comment