Performance(?) issues with ST_Reskew() (on rasters)

[Paul Ramsey]

If you provide a dump of a “good” raster, and a “bad” raster, and the exact SQL you are running, the odds of someone duplicating your issue and then fixing your issue go up 10-fold. I like fixing problems, not trying to replicate problems. 
ATB,
P

> On Feb 24, 2025, at 7:38 AM, Frank Gevaerts <frank.gevaerts at fks.be> wrote:
> 
> Hello,
> 
> I'm having issues with ST_Reskew(). The source raster (32BSI) contains 150000 points, and ST_Reskew() takes forever. If I rescale the raster to anywhere under ~80000 points, it suddenly only takes around 300ms. This is not linear, ~85000 points is bad, and then suddenly 80000 points is good.
> 
> I'm not actually sure if it's "just" a performance problem or an infinite loop, I have not had the patience yet to have it run for more than 20 minutes.
> 
> This is using postgis 3.5.2 on debian installed from apt.postgresql.org, and libgdal36 3.10.2
> 
> Is there anything I'm overlooking, or is there a memory usage parameter I can set to help with this?
> 
> Frank