Comment 216 for bug 197762

Revision history for this message
uMac (uvaio) wrote : Re: file transfers on USB disk are very slow

2.6.31-16-generic #53-Ubuntu x86_64 Did not fix anything for me ;o(

I did some further testing and the problem appears to be related to per file transfer and also to USB stick you use.

I did test with
1. Kingston micro SD HC 8GB memory card using with mini usb card reader.
    trasfered about 500MB of 700MB file then speed decreased to very very low almost stopped.
2. Kingston 8GB Traveler USB memory stick
    Transfered 700 MB file quickly but in the very end it took 2 minutes to complete transfer even it shown all 700MB copied.
    Then I tried 3 files of 700MB each in batch copy. And result is interesting. Overall speed was linearly decreasing from about 20MB/s to final 4 MB/s. After each about 700MB of transfer it got in about 2 minutes wait. Like copied 700, then progress didn't move for a while at all, copied another 700MB and then progress stayed at 1.4GB for another about 2-3 minutes. then last file transfered and waited again at the end.
I think the overall speed (I guess measured as average) may be decreasing as result of waiting at the end of file transfer.
I think it's doing the same thing with both memory cards it just does happen after different amount of data transfered.