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Re: THREDDS and grib

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  • Subject: Re: THREDDS and grib
  • Date: Thu, 24 Apr 2008 09:36:16 -0600
Hi Kevin:

I havent had time to reproduce this yet, but im guessing one source of the
slowdown is using opendap
URLS in the compound aggregation. It would be interesting to time 1) the single
aggregations, 2) the
compound agg as it exists, and 3) the compound agg, but replace the opendap
URLs with direct netcdf
files,

see attached file

Replace:

<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";>
  <aggregation type="union">
     <netcdf
     
location="http://data1.gfdl.noaa.gov:8780/thredds/dodsC/pr_daily_20C3M-1_R1_18610101-20001231";
     />
     <netcdf
     
location="http://data1.gfdl.noaa.gov:8780/thredds/dodsC/tasmax_daily_20C3M-1_R1_18610101-20001231";
     />
     <netcdf
     
location="http://data1.gfdl.noaa.gov:8780/thredds/dodsC/tasmin_daily_20C3M-1_R1_18610101-20001231";
     />
   </aggregation>
</netcdf>

With:

<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";>
  <aggregation type="union">

       <netcdf>
         <aggregation dimName="time" type="joinExisting">
           <netcdf
           
location="file:/data/gfdl_cm2_1/CM2.1U-D4_1860-2000-AllForc_H1/pp/atmos/ts/daily/tasmax_A2.18610101-19001231.nc"
           ncoords="14600" />
           <netcdf
           
location="file:/data/gfdl_cm2_1/CM2.1U-D4_1860-2000-AllForc_H1/pp/atmos/ts/daily/tasmax_A2.19010101-20001231.nc"
           ncoords="36500" />
         </aggregation>
       </netcdf>

       <netcdf>
         <aggregation dimName="time" type="joinExisting">
           <netcdf
           
location="file:/data/gfdl_cm2_1/CM2.1U-D4_1860-2000-AllForc_H1/pp/atmos/ts/daily/tasmin_A2.18610101-19001231.nc"
           ncoords="14600" />
           <netcdf
           
location="file:/data/gfdl_cm2_1/CM2.1U-D4_1860-2000-AllForc_H1/pp/atmos/ts/daily/tasmin_A2.19010101-20001231.nc"
           ncoords="36500" />
         </aggregation>
       </netcdf>

       <netcdf>
         <aggregation dimName="time" type="joinExisting">
           <netcdf
           
location="file:/data/gfdl_cm2_1/CM2.1U-D4_1860-2000-AllForc_H1/pp/atmos/ts/daily/tasmin_A2.18610101-19001231.nc"
           ncoords="14600" />
           <netcdf
           
location="file:/data/gfdl_cm2_1/CM2.1U-D4_1860-2000-AllForc_H1/pp/atmos/ts/daily/tasmin_A2.19010101-20001231.nc"
           ncoords="36500" />
         </aggregation>
       </netcdf>

   </aggregation>
</netcdf>