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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>