[netcdfgroup] nc_open takes a long time to open a big file

Dear Experts,
I'm using netcdf-4.1.1-rc1 and hdf5-1.8.4-patch1 on a 64-bit linux server running CentOS-5.5.
I have a netcdf-4 file that is 18404502496 bytes large.

My file's dimensions look like this:
        lon = 320 ;
        lat = 160 ;
        lev = 11 ;
        time = 1581 ;

It has 7 variables that look like this:
   float temp(time, lev, lat, lon) ;
                temp:_Storage = "chunked" ;
                temp:_ChunkSizes = 1, 1, 160, 320 ;
                temp:_DeflateLevel = 1 ;
                temp:_Shuffle = "true" ;

and 1 variable that looks like this:
    float sfp(time, lat, lon) ;
                sfp:_Storage = "chunked" ;
                sfp:_ChunkSizes = 1, 160, 320 ;
                sfp:_DeflateLevel = 1 ;
                sfp:_Shuffle = "true" ;

Is it normal for nc_open to take 20 seconds to open this file before returning control to my C program?

--Jennifer


--
Jennifer M. Adams
IGES/COLA
4041 Powder Mill Road, Suite 302
Calverton, MD 20705
jma@xxxxxxxxxxxxx



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