so here's a wierd one

Steve Emmerson steve at unidata.ucar.edu
Tue Apr 3 09:30:06 MDT 2007


Tyler,

May I suggest using the "pqcat" utility to investigate whether or not 
the data-products in which you're interested are created evenly in time 
or in batches.  For example

     pqcat -vl- -f WMO -p 
"((WF|WO|WU|WR|WW|WG|AC|NW)US)|^S[AP]|^S[NS]|^WT(PZ|PN|PA|NT)|(^S[IMN]V[^GINS])|(^S[IMN]W[^KZ])|(^S(HV|HXX|S[^X]))|(^SX(VD|V.50|US(2[0-3]|08|40|82|86)))|(^Y[HO]XX84)|^ACUS11|/p(FTM|FWDDY)" 
 >/dev/null

Look at the creation-times.  Are they evenly distributed or bunched?

With apologies for line-wrapping,
Steve Emmerson

On Mon, 2 Apr 2007, Tyler Allison wrote:
> [for ldm-6.6.0 and ldm-6.6.2]
>
> If I use the following feed pattern [upstream = idd at wisc and bigbird at tamu]:
>
> request WMO
> "((WF|WO|WU|WR|WW|WG|AC|NW)US)|^S[AP]|^S[NS]|^WT(PZ|PN|PA|NT)|(^S[IMN]V[^GINS])|(^S[IMN]W[^KZ])|(^S(HV|HXX|S[^X]))|(^SX(VD|V.50|US(2[0-3]|08|40|82|86)))|(^Y[HO]XX84)|^A
> CUS11|/p(FTM|FWDDY)" upstream.server.edu
>
> the data seems to flow down to me in "chunks". What I mean by this is that
> is when I run 'ldmadmin watch' I see no data for between 4 and 10 minutes.
> Then all of a sudden the last 4-10 minutes worth of data comes down within
> a 3 second period. It then holds again...and 4-10 minutes later another
> payload of data comes down...etc...etc.
>
> If the *ONLY* thing I change is the feed pattern to:
>
> request WMO ".*" upstream.server.edu
>
> The data feed runs normal.
>
> I'm confused! I, and the upstream, have bandwidth to burn so I'm leaving
> the feed as ".*"...my pattern was attempting to conserve bandwidth for the
> upstream providers but it seems I did more harm than good.
>
> I havent totally verified this issue but it seems to be the culprit. Can
> anybody confirm?
>
> -Tyler
>
>



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