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Re: CONDUIT feed timing

Jerry,

I note that dcarchive.ssec.wisc.edu has redundant feed requests:
http://my.unidata.ucar.edu/cgi-bin/rtstats/iddstats_topo_nc?CONDUIT+dcarchive.ssec.wisc.edu
so, if the product were scoured out of your queue, you could receive it
again from the other route with the same checksum.

The pqmon output will show the oldest product in your queue (use the -i
option to output at periodic intervals. If your queue size is smaller
than what you wan hold under normal lateny conditions, then you might
receive a product twice. Eg, if pqmon showed that your oldest product
was 1800 seconds old, and you had a latency greater than 1800 seconds,
then you could accept the product when offered it from the other
upstream host (up to your rpc.ldmd maxtime, eg 3600 seconds by default
which is more strictly enforced in LDM 6.1).

Steve Chiswell
Unidata User Support


On Wed, 2005-01-05 at 14:04, Jerrold Robaidek wrote:
> Hi Steve,
> 
> We did receivie the 18Z GFS 1 degree grib files more timely (more than 30 
> minutes earlier 
> than in the recent past)
> 
> However, we did notice that we had some duplicate grib messages being 
> received.
> 
> 
> 
> here is a portion of wgrib output
> 
> 563:46852448:d=05010412:SPFH:kpds5=51:kpds6=105:kpds7=2:TR=10:P1=0:P2=0:TimeU=1:2
>  m above 
> gnd:anl:NAve=0
> 564:46950272:d=05010412:SPFH:kpds5=51:kpds6=105:kpds7=2:TR=10:P1=0:P2=0:TimeU=1:2
>  m above 
> gnd:anl:NAve=0
> 565:47048096:d=05010412:PRES:kpds5=1:kpds6=243:kpds7=0:TR=10:P1=0:P2=0:TimeU=1:convect-cld
>  
> top:anl:NAve=0
> 566:47069774:d=05010412:PRES:kpds5=1:kpds6=243:kpds7=0:TR=10:P1=0:P2=0:TimeU=1:convect-cld
>  
> top:anl:NAve=0
> 567:47091452:d=05010412:5WAVA:kpds5=230:kpds6=100:kpds7=500:TR=10:P1=0:P2=0:TimeU=1:500
>  
> mb:anl:NAve=0
> 568:47197420:d=05010412:5WAVA:kpds5=230:kpds6=100:kpds7=500:TR=10:P1=0:P2=0:TimeU=1:500
>  
> mb:anl:NAve=0
> 
> note: 567 and 568 have the same checksum
> 
> dcarchive{oper}:cksum 567.out
> 3643681194 105968 567.out
> dcarchive{oper}:cksum 568.out
> 3643681194 105968 568.out
> 
> 
> Shouldn't one of these not have come through?
> 
> Jerry
> 
> Steve Chiswell wrote:
> > Jerry,
> > 
> > Yesterday at 1830Z we implemented a parallel queueing scheme at the
> > NWS that we hope will improve the timeliness of data being ingected into
> > the CONDUIT data stream. Any feedback you can provide on how
> > this affects your reception would be greatly appreciated.
> > 
> > Since data will be inserted in parallel, you will notice that multiple 
> > model runds and forecast times will probably be interspersed where
> > previously they had been serialized.
> > 
> > I watched the 00Z GFS last night, and the posting gap between f084 and
> > f132 was matched on the FTP server at 0422Z and later at 0509Z, the
> > other grids were posted to the NWS servers, so all appears to be
> > behaving correctly on this end.
> > 
> > Steve Chiswell
> > Unidata User Support
>