nishant mungse [nishantmungse@xxxxxxxxx] wrote: > Hi, > > I've created a device mapper target and I wanna test its read and > write mechanisms. I created a device using this target and tried to > write a filesystem on to the device. > > My target is creating roughly two outgoing bios per incoming bio. > Which is maybe why I'm not able to get a proper log after running the > mke2fs command as while writing the filesystem, there are massive > amounts of writes performed on the device. > > So, I tried to use the cat command to directly write to the device > file. The write is being performed for sure because I'm able to view > the data written to the underlying device. > > But there is no output when I try to read the device file contents using cat. > > Is there any other way to test the read/write workflows of a dm target > that can give out a proper log ? I am not sure what you mean by 'proper log'. I would use 'dd' with direct I/O to avoid cache so that every read and write directly go to the device. I don't think you can do that with 'cat' command. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
