[Sugar-devel] Sugar 0.110 (Build 20) shows unexplained stoppage of io on removable drives

[Tony Anderson]

I have spent hours in the past few days coping with io failures while 
installing rpms and copying large files from usb sticks. The problem has 
also affects sd cards.

The symptom is that during an extended io operation, the usb stick 
generates io errors. An 'ls' on the folder shows it to be empty. After a 
cd ../ and a cd back to the folder, the ls shows the contents. This 
failure has been seen on an sd card as well. It does not occur during 
flash so the firmware appears unaffected. Since the io recovers, it is 
not a simple 'umount'.

My theory is that the problem is related to the power settings. The 
gsettings: org.sugarlabs.power automatic claims the default to be false.
However, in 0.110 it is set to true. One basis for the theory is that 
when the script appears stalled, hitting the enter key seems to move it 
forward (awaking the system?).

After resetting the value to false, access to usb devices appears more 
reliable but there has been at least one script failure that may be due 
to this problem.

Since the problem seems to be related to extended io operations when 
there is no interactive use of the keyboard or trackpad, this could have 
devastating consequences for use of an XO as a server.

Tony