On Tue, Jan 29, 2013 at 09:37:08AM +0100, Alessandro Zappala wrote: > > [1.] Low speed when > transferring files over USB flash drives > > [2.] Bug > Description > > Low speed when transferring files over USB 2.0 > and USB 3.0. Example USB flash devices with FAT that demonstrates > this problem: > > ID 13fe:4100 Kingston Technology Company > Inc. > > ID 090c:1000 Silicon Motion, Inc. - Taiwan (formerly > Feiya Technology Corp.) 64MB QDI U2 DISK > If the USB drive is not > empty, the transferring speed is lower. the bigger the file, the > slower the speed. Here are my tests: > from HDD to USB (FAT): > > 1. > 450 MB in 4 sec. (USB sitck EMPTY) 112.5 MB/s Are you sure you just aren't hitting the issue that once the kernel buffers are full, they then write out to the device itself? Doing speed tests without disabling buffering, and making sure that the FAT flush option is enabled, is not a good idea at all. Lots of USB flash devices, including older ones like this one, were quite slow. > DistroRelease: Ubuntu 12.04 > > Package: > linux-image-3.2.0-32-generic 3.2.0-32.51 As you are using a distro, please work with them on this issue, there's nothing that we can directly do about it. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
