Alan I used usbmon to gain more visibility and i see some interesting points in it. I am reproducing a small and relevent portion of usbmon log below. Note that the test comprises of writing about 12Mbytes of data to 2.0 external USB hard disk.
1 810c73e0 1314291816 C Bi:002:01 0 13 D 5 2 810c73e0 1314296816 C Bo:002:02 0 31 D 6 3 810c73e0 1314302816 C Bo:002:02 0 31 D 7 4 810c73e0 1314309816 S Bo:002:02 -150 31 D 3 5 810c73e0 1314312816 C Bi:002:01 0 13 D 6 6 81485200 1314318816 C Bo:002:02 0 512 D 5 7 810c73e0 1314323816 C Bi:002:01 0 13 D 8 8 81485200 1314331816 C Bo:002:02 0 512 D 5 9 810c73e0 1314336816 C Bi:002:01 0 13 D 30001 10 81485200 1344337816 C Bo:002:02 -131 0 0 11 810c73e0 1344337816 S Co:002:00 -150 0 1 12 810c73e0 1344338816 C Co:002:00 0 0 6001 13 810c73e0 1350339816 S Co:002:00 -150 0 1 14 810c73e0 1350340816 C Co:002:00 0 0 0 15 810c73e0 1350340816 S Co:002:00 -150 0 1 16 810c73e0 1350341816 C Co:002:00 0 0 0 17 810c73e0 1350341816 S Bo:002:02 -150 31 D 1 18 810c73e0 1350342816 C Bo:002:02 0 31 D 0 19 810c73e0 1350342816 S Bi:002:01 -150 13 D 539 20 810c73e0 1350881816 C Bi:002:01 -32 0 3 21 810c73e0 1350884816 S Co:002:00 -150 0 1 22 810c73e0 1350885816 C Co:002:00 0 0 6 23 810c73e0 1350891816 S Bi:002:01 -150 13 D 1 24 810c73e0 1350892816 C Bi:002:01 0 13 D 1 25 810c73e0 1350893816 S Co:002:00 -150 0 1 26 810c73e0 1350894816 C Co:002:00 0 0 6000 The rightmost column above is difference between timestamp in milliseconds. As you see, the difference in timestamp for the first 7 samples looks ok. However there is big jump of about 30 seconds in timestamp between sample #8 and #9. Similarly the timestamp difference between sample #25 and #26 is about 6 seconds. I see many such random jump in the timestamp in the usbmon log that i captured for the entire data transfer. The net result is that the copy operation takes long time to complete. Now my questions are 1. What could possibly be the reason behind the abrupt jump in the time stamp values ? 2. Are there any error codes in usbmon log that i should grep for in order to gain more visibility ? 3. Is this a known issue in 2.6.12 series kernel and is there any fix for the same ? I can provide entire usbmon log(contain 2074 lines) if that make the issue more clear. BTW,the usbmon is an excellent tool. Regards Vivek -----Original Message----- From: Alan Stern [mailto:[EMAIL PROTECTED] Sent: Wednesday, May 31, 2006 6:48 AM To: Vivek Dharmadhikari Cc: linux-usb-devel@lists.sourceforge.net Subject: RE: [linux-usb-devel] Usb hangs during small and large file transfer On Tue, 30 May 2006, Vivek Dharmadhikari wrote: > Hello Alan > > I was closely following the "resetting high speed usb device" thread and > i see that usbmon was used to track down the issue. I think usbmon could > be very helpful to debug the USB hangs issue that i reporeted earlier by > looking at the time stamps in usbmon log. I know that the documentation > exists for usbmon exists in Documentation/usbmon.txt. Actually it's in Documentation/usb/usbmon.txt. > But the document > do not talk about idnetifying the time stamps in the usbmon log. Yes it does. The timestamps are written as integers, in units of microseconds. > Is there any utility/tools that parse the usbmon output in human > readable format ? No. > Is there any easy way to interprete the usbmon log ? Not if you don't already understand it. Alan Stern _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
