Memory Stick Duo Space Issues?

[deaninho]

hi everyone,

i've just got a P900 and also bough a 128mb Memory Stick Duo card specifically so i can put MP3's on it. However, i've put about 70megs worth of MP3 onto the card and its already telling me that i've used all the space up on there? Does anyone know why this is happening, is there some kind of uncompression happening on the MS Duo ? i look forward to your thoughts and replies :)

[Shun]

If I am not wrong, P900 uses FAT16, a filesystem that was used in MS-DOS, it was later enhanced to FAT32 in Windows 9x to handle larger harddisk.

Many filesystem allocate storage in blocks for storing data called cluster, it gets bigger as the size of the storage increases.

In such filesystem, even a 1 byte file uses 1 cluster.

On cluster size of 32768 bytes, a file with a size of 32767 bytes uses 1 cluster, efficiency is more than 99%. A file of 32769 bytes will uses 2 clusters, which is 65536 bytes, efficiency is 50%. A file of 1 byte will still uses 32768 bytes, efficiency is less than 1%!

FAT16 default cluster is very large on a 128MB storage, so the wastage is very high too.

FAT32 uses cluster more efficiently, but it is slower than FAT16.