[gdal-dev] limiting drivers that get registered

[Ben Elliston]

On 27/03/18 22:00, Even Rouault wrote:

> Ah that was apparently your actual need rather than limiting the number of 
> drivers per-se. Do you have profiled where time was lost if you find opening 
> too slow ? The identification logic of drivers is supposed to operate fast 
> (extension based, or on the content of the first kilobyte of the header), but 
> there might be some drivers where improvements can be done.

I wrote a pathological benchmark that opened and closed an HDF5 file
10,000 times. Moving the HDF5 driver to the head of the driver list gave
about a 5x speedup.

Thanks for the idea earlier. I came up with an acceptable solution:
register all drivers, look to see which ones are present by using
GDALGetDriverShortName(), and then de-register all the drivers.

Cheers, Ben