What does "Faustian bargain" mean?

In an article I see this phrase "Faustian bargain". Both I and my teacher were unable to translate or understand it. Can you help me and explain this phrase?

Context:

The reason for linking all the modules together in a single address space, with no protection between the modules, is that designers have made a Faustian bargain: better performance at the cost of more system crashes. We will quantitatively examine the price of this trade-off below.

This comes from the first page of this work: http://docs.huihoo.com/minix/reliable-os.pdf or http://74.125.155.132/scholar?q=cache:_sabEZ3IFvsJ:scholar.google.com/&hl=en&as_sdt=0,5 (preloaded as google html view)

'Faust' is the main character in German legend. From Wikipedia:

Faust or Faustus (Latin for "auspicious" or "lucky") is the protagonist of a classic German legend. Though a highly successful scholar, he is unsatisfied, and makes a deal with the devil, exchanging his soul for unlimited knowledge and worldly pleasures.

Making a 'Faustian bargain' can be interpreted as making a deal with the devil - it may seem like a good deal, but there is always a catch, and that catch is usually very, very bad.

Here is a wikipedia article discussing 'Deals with the Devil', which they also term as a 'Faustian bargain':

http://en.wikipedia.org/wiki/Deal_with_the_devil