[OpenAFS] Network becomes terribly slow when cache manager flushes updates over xDSL
Simon Wilkinson
sxw@inf.ed.ac.uk
Wed, 8 Jul 2009 13:12:47 +0100
One interesting project, for someone who's looking to write something
really useful for OpenAFS, would be to implement path MTU discovery.
This was original an idea for this year's Summer of Code, and it's
description there read ...
OpenAFS uses a UDP based RPC transport called Rx. RX uses the endpoint
maximum transfer units (MTUs) to determine how large a packet may be
transmitted without requiring the packet to be broken into fragments
on its journey. The prevalence of IP tunnelling, typically with
reduced MTUs, on modern internet topographies, means this is often not
an accurate way to determine true maximum packet size. This project
would develop and integrate into Rx a mechanism to discover the MTU of
the path rather than merely the endpoints, resultingly tuning packet
sizes accordingly.
Cheers,
Simon.