It's helpful to know the abstract for Larry's talk before watching:<p><pre><code> DESCRIPTION
CPython's GIL means your Python code can only run on one CPU core at a
time. Can we remove it? Yes, we can... in fact we already have! But is it
worth the cost?
ABSTRACT
CPython's "Global Interpreter Lock", or "GIL", was added in 1992. It was
an excellent design decision. But 24 years is a long time--today it
prevents Python from capitalizing on multiple CPUs. Many people want us to
remove the GIL.
It turns out, removing the GIL isn't actually that hard. In fact, I
already removed it, in my experimental "gilectomy" branch. But the GIL is
one reason CPython is so fast! The "gilectomy" makes CPython shockingly
slow.
This talk will discuss the history of the GIL, how the GIL helps make
CPython fast, how the "gilectomy" removed the GIL, and some ways we might
be able to make the "gilectomy" version fast enough to be useful.
</code></pre>
from <a href="https://us.pycon.org/2016/schedule/presentation/2101/" rel="nofollow">https://us.pycon.org/2016/schedule/presentation/2101/</a>