id summary reporter owner description type status priority milestone component version severity resolution keywords cc 3459 Bad output buffer sizing while warping warmerdam Even Rouault "I am seeing very slow gdalwarp in some cases apparently due to poor selection of the output buffer size. I suspect the problem relates to r18035 and it does not occur in 1.6, though it does happen in 1.7 and trunk. The command is: {{{ gdalwarp -rn -te -4000000 -3000000 0 3000000 -t_srs '+proj=gnom +lon_0=-90.0 +lat_0=58 +a=5500000 +b=5500000' -tr 2000 2000 bug3458.tif out.tif -co TILED=NO }}} the input is: {{{ Driver: GTiff/GeoTIFF Files: bug3458.tif Size is 21600, 21600 Coordinate System is: GEOGCS[""WGS 84"", DATUM[""WGS_1984"", SPHEROID[""WGS 84"",6378137,298.257223563, AUTHORITY[""EPSG"",""7030""]], AUTHORITY[""EPSG"",""6326""]], PRIMEM[""Greenwich"",0], UNIT[""degree"",0.0174532925199433], AUTHORITY[""EPSG"",""4326""]] Origin = (-180.000000000000000,90.000000000000000) Pixel Size = (0.008333333333333,-0.008333333333333) Metadata: AREA_OR_POINT=Area Image Structure Metadata: INTERLEAVE=PIXEL Corner Coordinates: Upper Left (-180.0000000, 90.0000000) (180d 0'0.00""W, 90d 0'0.00""N) Lower Left (-180.0000000, -90.0000000) (180d 0'0.00""W, 90d 0'0.00""S) Upper Right ( 0.0000000, 90.0000000) ( 0d 0'0.01""E, 90d 0'0.00""N) Lower Right ( 0.0000000, -90.0000000) ( 0d 0'0.01""E, 90d 0'0.00""S) Center ( -90.0000000, 0.0000000) ( 90d 0'0.00""W, 0d 0'0.01""N) Band 1 Block=21600x1 Type=Byte, ColorInterp=Red Band 2 Block=21600x1 Type=Byte, ColorInterp=Green Band 3 Block=21600x1 Type=Byte, ColorInterp=Blue }}} The output includes many tiny output buffer regions like: {{{ GDAL: GDALWarpKernel()::GWKNearestNoMasksByte() Src=634,2161,631x1766 Dst=0,0,1000x1 0GDAL: GDALWarpKernel()::GWKNearestNoMasksByte() Src=1259,406,9542x1757 Dst=1000,0,1000x1 GDAL: GDALWarpKernel()::GWKNearestNoMasksByte() Src=637,2162,634x1765 Dst=0,1,1000x1 }}} I would note the behavior is very different with TILED=YES in the creation switches. " defect closed normal 1.7.2 Algorithms 1.7.0 normal fixed warper