Red Hat Bugzilla – Bug 70014
Severe system degradation when displaying random data
Last modified: 2008-05-01 11:38:03 EDT
Description of Problem:
catting a binary file or /dev/urandom causes gnome-terminal to consume large
amounts of resources, enough to make the system difficult to use.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. cat /dev/urandom or a binary file
Severe system degradation
Snappy display of random trash
Not sure if this is a bug or a "don't do that then" ...
There's already an open bug to improve VTE performance, probably this is a dup
of that if anything. Of course improved VTE performance may well hose your
system more by sucking off of /dev/urandom more quickly and making more system
This should be fixed in 0.7.4 and later. (Basically what was happening was that
the terminal detected bogus multibyte input, munged the first bogus byte into
'?', read some more text from the child process, and then started again. When
catting /dev/urandom, this would build up more pending data with each iteration,
leading to horrible slowdowns.)
I'm still seeing gnome-terminal eating CPU for breakfast when I do 'cat
/dev/urandom' with vte-0.8.10-1 . . . am I missing something here?
Jay, when you break out of catting /dev/urandom, the terminal should recover
almost instantly. Previously it would still be attempting to work through a
considerable backlog of garbage data, and would remain unresponsive, even if you
told gnome-terminal (via its menu) to reset.
OK, I misunderstood the problem. Indeed, as soon as you hit CTRL-C the process
exist and the system recovers, so this is resolved.