Terminal Randomly Freezes

[rdJB8wd]

Problem:
When running an application (for example via a launcher with terminal or straight from a terminal instance), the terminal randomly freezes. That is, the output stops in mid-stream after a random period.Terminal Freeze Screenshot from 2013-09-26 11:54:09.png

I discovered this while trying to run some long-running machine learning applications using a terminal.

Can anyone else reproduce this?

Terminals Affected:
gnome-terminal
mate-terminal

Confirmed:
Occurs with python test applications (see code below) or java applications. This also occurs randomly. See the sample code below (save to file and execute in a terminal). Using this code you can see the output freezes perhaps after a few minutes. In other words, the terminal scrolls output and then just stops mid-stream. To resume, you either need to:

1. expressly select reset & clear or
2. double click on the terminal window or
3. UNRELIABLE--possibly just try to scroll back and fourth.

What I Tried:
Using various terminals, I have tried setting scrollback on, off, unlimited, or 512 lines--in other words, I have tried everything that I am aware to avoid some type of obvious "buffer" issue. I have also written teh test case below. Oddly, this occurs in any of the GUI terminals--but MIGHT not occur with xterm (I have never seen the issue occur with xterm so far).

Test Code:

import time

starttime = time.time()

i = 0

while(True):    
    i = i + 1
    print("Still working " , i, " " , time.time() - starttime)

Specs:
Ubuntu 13.04
MATE 1.6 (but also occurs in Ubuntu Default, GNOME3, etc.)
i7
32Gb memory
NVidia 760

[rdJB8wd]

Possible Resolution:

I confirmed that the terminal freezes randomly when running a terminal instance such as MATE Terminal or GNOME Terminal. The freezing or stopping did not occur with XTerm.

This lead me to think that this was a video issue. Because I am using a new video card (Nvidia GTX 760) as of August 2013, I started to investigate the video card driver itself. I was apparently using an older version of the Nouveau Driver. I did not install the Nvidia proprietary drivers (currently 3.25).

I uninstalled Ubunut Nvidia Current and installed Nvidia 319 using Syntaptics (the option does not appear in Ubuntu SoftwareCenter). The install, even on a high-end machine took quite some time. I then selected the Additional Drivers and the NVIDIA binary xorg driver (NOT Nouveau). Again, this took a while to make the change.

Subsequent testing using the above test Python code shows the video driver update resolved the problem.