On Fri, 10 Apr 2015, Steve Bangert wrote: > > > The reason i ask is that the performance of the drive seems slow and > > > there were intermittent hangs during transfers based on my limited use > > > of the drive so far. Steve > > > > Does this happen with both the uas and usb-storage drivers or only with > > one of them? > > Both of them, i have a unpacked kernel on the drive and would do a copy > and paste into another directory of the same drive, transfer speeds of > 50 MB/sec are good through about half way through the transfer event > then a hang occurs from this point on transfer speeds drop to 20MB/sec > and then slowly ramp down to less than 5MB/sec at the end of the file > transfer. this is with both uas and usb-storage. If there is a hang then no more data is getting transferred. Of course the average transfer speed will slowly decay to 0. > I have some traces, there very large and the mailing list filter will > reject them. so i will send them directly. The uas trace doesn't show a hang. It just shows a bunch of normal transfers. The usb-storage trace might show a hang, right at the end. The computer tried to read 13 sectors from the disk, and there was no response. But since this was at the end of the trace, it could simply be that you stopped the trace before the response arrived. Maybe the drive isn't causing this slowdown. Some other part of the system could be responsible. Alan Stern -- 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
