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Slow Downstream Node Problem

Hello there,

We've been experiencing the "pq_del_oldest: conflict" message
problem and reading the web page you have describing it got
me thinking that there must be a better solution for the 
slow or flaky network connection element.

The net result of the slow downstream feed is that the incoming
data is delayed (possibly lost) due to the inablity of ldm
to make space in the product queue by deleting the oldest data.
It seems to me that the downstream side of things should 
basically be told to disconnect and reconnect at the latest
(newest) end of your product queue. Better the for a customer
of your ldm to lose data than for you to, certainly for us anyway.

I started looking at the code and realised that this might not
be easy to do. After all how do you know which connection has 
obtained the resource lock? Then I thought that maybe you don't
have to know. If you signal the "pq_del_oldest: conflict" to the
process group , i.e. Let everyone know you've seen EAGAIN, then
in handling the signal the process checks the following:

1. Does it have a lock? If not continue
2. If so is the lock on the oldest queue member? If not continue
3. If it is the oldest, free the resource, reset the pq cursor and
disconnect from the peer.

I was thinking about trying to implement this but I don't have
anytime available, certainly not in the near future, so I was
wondering if you've been considering this?

Paul.

-- 
Paul Hamer
phone: 303.497.6342