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Re: 19990716: CONDUIT latencies

David,
      The retention time of products can be incresed.
But, then the product queue size has to increase as well.
If everybody else is willing I am too.
David

> 
> > 
> > Chiz,
> > > 
> > > There are some things we can do to tune the LDM requests,
> > > and we can look at other upstreams. 
> > > 
> > > There is currently 1 bottle neck that drives the initial latencies up.
> > > This is the T-1 line from NCEP to GSFC which is roughly capable of
> > > delivering 550MB per hour. Since the AVN (now out to 84 hours) can exceed
> > > 600MB, and the MRF is also pushing 500MB then things can get backlogged-
> > > especially when NCEP has Cray crashes and then come back up and post
> > > the data all at once.
> > 
> > Not much we can do about that one (at least for now).
> 
> 
> Yes, looking at the latency plots, it frequently goes over 3600s
> coming in to Unidata.  So, it follows that its going to be
> late everywhere else.
> 
> > > 
> > > For the past month we have also been downgraded from out 100baseT
> > > connection to a 10baseT connection while our building is rewired.
> > > When our switch gets moved to the new wiring closet it could improve
> > > things as well.
> 
> Trying to shove this much data (incoming, plus several outgoing copies)
> through the one 10baseT connection to flip.unidata.ucar.edu is probably
> also not going to help. 
> 
> 
> Considering that >3600 latencies are going to be common for
> a while, can LDM be made to hold on to it longer?  An 1hr 10minutes
> late is better than never at all...especially when its right near
> the edge and drops some but not all a set of products.
> 
> 
> 
> 
> --------------------------------------------------------
>  David Wojtowicz, Research Programmer/Systems Manager
>  Department of Atmospheric Sciences Computer Services
>  University of Illinois at Urbana-Champaign
>  email: address@hidden  phone: (217)333-8390
> --------------------------------------------------------
> 
> 
> 
>