Defer RPC/IMD loading for GeoTiff
Need better performance opening GeoTiff? files when there are thousands of files on a network share. In a previous version of GDAL (1.6.0), setting GDAL_DISABLE_READDIR_ON_OPEN resulted in very good performance for this scenario. In 1.8.0 setting this variable made matters worse. It was determined that searching for the various metadata files on Open was causing the slow-down. Even Rouault provided a patch that deferred loading of RPC and IMD until necessary (that is to say when GetMetadata?() or GetMetadataItem?() is called with "RPC" or "IMD" metadata domain, or when GetFileList?() is called. I tested this patch in 1.8.0 and got satisfactory results. Please add this patch to the 1.8.0 tree and future versions of GDAL. I will try to attach the patch.
Change History (5)
changed from warmerdam to Even Rouault