by Мастер » Thu Aug 09, 2012 8:38 am
Well, I ended up doing a somewhat different experiment.
Copied a folder, containing > 140 sub-folders, and > 28,000 files (mostly pretty small), from the internal NTFS-formatted hard drive to the FAT-formatted USB flash drive. Both experiments conducted on the home Dell desktop, a few years old.
Booted up in a home-brew Linux - copying the folder and the contents took just under 7.5 minutes. Compared the contents, using the "diff" command, didn't time it, but it seemed pretty quick. (Probably less than one minute.)
Booted up in Windows XP - just deleting the contents is taking many, many times as long as copying them there under Linux did. More than 30 minutes, and according to the progress bar, still only a small fraction of the job is completed.
Haven't run a controlled experiment on the HP laptop craputer, running Windows 7, but anecdotally have found copying to/from the flash drive to be painfully slow.
My speculative conclusion - it is not FAT per se that sucks, but the Windows driver for FAT. I suspect it is not buffering anything in memory - each of the little files that get copied, the entire block of memory gets loaded from the flash drive into RAM, is then modified in RAM, and then written back to the flash drive, even if the file only takes up a small piece of one block of memory. Whereas Linux does buffering, keeping recently used flash memory pages in RAM, so the block doesn't actually get written back to the flash drive until after it is completely modified, probably with many of the little files.
At least, that's my best guess.
They call me Mr Celsius!