GeoTIFF-BigTIFF writer is very slow when saving metadata


Saving an output of a subset graph (Read > Subset > Write) as a GeoTIFF-BigTIFF is very slow (2.6 minutes, 259 B/s, 128 pixels/s) even though the output is only 2 bands and 100x100 pixels (29 MB).

Changing the output format to GeoTIFF (or to other formats) and keeping all the other parameters the same speeds things up significantly (3 seconds, 13504 B/s, 6666 Pixels/s).

It only seems to be the case when copy metatada is set to true in the Subset operator. When it is set to false then writing of GeoTIFF-BigTIFF is as fast as for other formats.

Tested on SNAP 5.0.1 with a S2 scene previously resampled to 60 m.



I’ve heard before that it is sometimes slow.
But the information that it is only slow if the “Copy Metadata” is enabled is new.
This might be helpful. I’ve created an issue (SNAP-685) for it.

Thanks for the report.