On Sat, Jul 06, 2019 at 11:33:27AM +0200, Andrea Vai wrote: > On 03/07/19 14:36:05, Ming Lei wrote: > > On Wed, Jul 03, 2019 at 07:11:17AM +0200, Andrea Vai wrote: > > > On 03/07/19 10:01:23, Ming Lei wrote: > > > > On Wed, Jul 03, 2019 at 12:39:31AM +0200, Andrea Vai wrote: > > > > > On 02/07/19 20:01:13, Ming Lei wrote: > > > > > > On Tue, Jul 02, 2019 at 12:46:45PM +0200, Andrea Vai wrote: > > > > > > > Hi, > > > > > > > I have a problem writing data to a USB pendrive, and it seems > > > > > > > kernel-related. With the help of Greg an Alan (thanks) and some > > > > > > > bisect, I found out the offending commit being > > > > > > > > > > > > > > commit f664a3cc17b7d0a2bc3b3ab96181e1029b0ec0e6 > > > > > > > > > > > > > > [...] > > > > > > > > > [...] > > Then could you install bcc package and collect the IO trace? > > > > sudo /usr/share/bcc/tools/biosnoop | grep sdN > > > > sdN is your USB disk device name. > > The command runs forever (or at least for hours) without giving any output through "|grep sdf". The device is connected, but not mounted. Maybe I should run the command with the device mounted? Or while performing the test? > The command itself seems to work, as /usr/share/bcc/tools/biosnoop | tee -a biosnoop.txt produces an output file sized about some MB in some hours. > > What should I do? 1) run the bcc biosnoop trace in one terminal after mounting the fs on the USB dirve 2) start the write test in another teminal 3) wait for 10 seconds, and stop the bcc trace via ctrl^ + C, then post the bcc biosnoop trace log Thanks, Ming
