SD Card imports are very slow. much slower than what reading from the SD card should be.
I suspect that the importer checks each file using either or more of
a) file size
b) checksum
to determine which files to import and which are duplicates,
Ny suspicion is that the checksumming reads the while file.
That sounds counterproductive. It should really just checksum an initial 1K or such
and only if that matches that of another candidate file, go one order of magnitude larger (1k, then 100k, then 1B etc) until it finds a difference or hass checksummed the whole file
That would greatly speed up imports I gather
(or course it would need to keep a database of the relevant checksums with each imported file)
I have the same experience as you before.
I can tell you that is not due to checksum or anything,
it’s because this stuff will spend 90% or more CPU to generate thumbnail during file transfer.
Worst comes to the worst, the high CPU usage will make the machine overheat, then everything getting slower and slower…
It’s an unwise strategy (similar case also found in some bad design NAS).
I fixed it by modifying the internal script, just postpone the thumbnail generation process after all file transferred. The performance improvement is over 30%.
