EXTREME slowdown

[Stefan Gofferje]

Hi,

Arlindo da Silva schrieb:

> Which "file"? Is this by any chance a internally compressed HDF-4 or
> GRIB-2? Some formats implement compression on a layer by layer basis.
> So, even if you need a single horizontal point you have to read the
> whole xy slice, decompress it, and then take your single point. So,
> these compression techniques are not optimized for single point access.

Exactly this:

http://nomad5.ncep.noaa.gov:9090/dods/gfs/gfs20080216/gfs_06z

Funny is: If I just do some 'd tmp2m-273.16', it's drawn in milliseconds
without any waiting. So the delaying part is highly likely the define
stuff. Especially, if you run the script when something already is on
the canvas. Between calling the script and the clearing of the canvas is
the delay, so this is another hint that the define-stuff causes the delay.

Version:

Grid Analysis and Display System (GrADS) Version 1.9.0-rc1
Copyright (c) 1988-2007 by Brian Doty and IGES
Center for Ocean-Land-Atmosphere Studies (COLA)
Institute for Global Environment and Society (IGES)
GrADS comes with ABSOLUTELY NO WARRANTY
See file COPYRIGHT for more information

Config: v1.9.0-rc1 32-bit little-endian readline sdf/xdf netcdf dap
dap-stn lats athena printim

--Stefan