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WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:00:00.506 --> 00:00:15.486 A:middle
[ Silence ]
00:00:15.986 --> 00:00:24.516 A:middle
>> Well, good morning
and welcome.
00:00:24.516 --> 00:00:25.276 A:middle
[ Applause ]
00:00:25.276 --> 00:00:28.246 A:middle
>> I'm Bud Tribble, Vice
President of Software Technology
00:00:28.246 --> 00:00:29.456 A:middle
at Apple and I'm going to talk
00:00:29.456 --> 00:00:32.566 A:middle
about maximizing
battery life in OS X.
00:00:34.556 --> 00:00:41.206 A:middle
Now, you know, battery
life is just a key feature
00:00:41.206 --> 00:00:42.016 A:middle
for customers.
00:00:42.016 --> 00:00:45.146 A:middle
I know its key for me,
I know its key for you.
00:00:45.146 --> 00:00:48.506 A:middle
And as you can tell from
our key note sessions,
00:00:48.956 --> 00:00:51.596 A:middle
battery life is one of the
places where we put a lot
00:00:51.596 --> 00:00:53.636 A:middle
of focus in OS X Mavericks.
00:00:54.136 --> 00:00:58.546 A:middle
And the reason is simple,
mobility is a key feature
00:00:58.546 --> 00:01:02.156 A:middle
for our customers and battery
life is key for mobility.
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:00:58.546 --> 00:01:02.156 A:middle
for our customers and battery
life is key for mobility.
00:01:02.816 --> 00:01:08.686 A:middle
Now, mobility has always
been an important feature.
00:01:09.726 --> 00:01:11.666 A:middle
However, the user experience
00:01:11.666 --> 00:01:13.596 A:middle
for mobility is not
always been great.
00:01:13.596 --> 00:01:16.896 A:middle
This is actually an Osborne
1, you probably don't--
00:01:16.896 --> 00:01:19.026 A:middle
most of you probably
don't remember
00:01:19.026 --> 00:01:20.386 A:middle
but the Osborne 1 was famous
00:01:20.386 --> 00:01:22.896 A:middle
for being the first computer
you could carry around with you.
00:01:23.306 --> 00:01:25.916 A:middle
However, even that in that
case because of the CRT
00:01:25.916 --> 00:01:28.526 A:middle
and other things, you had
to find a place to plug it
00:01:28.526 --> 00:01:30.836 A:middle
in as soon as you
wanted to use it.
00:01:31.406 --> 00:01:34.896 A:middle
Of course things have gotten
a lot better over the years
00:01:35.216 --> 00:01:40.956 A:middle
but nonetheless if you are
at 3 hours battery life
00:01:40.956 --> 00:01:44.446 A:middle
on your system, you're spending
most of your time just wondering
00:01:44.446 --> 00:01:46.736 A:middle
around looking for the next plug
and I'm sure you've all been
00:01:46.736 --> 00:01:48.886 A:middle
in the airport and that
sort of a situation.
00:01:49.536 --> 00:01:51.866 A:middle
Now, your battery life
will vary depending
00:01:51.866 --> 00:01:53.406 A:middle
on what you're doing of course.
00:01:53.766 --> 00:01:57.716 A:middle
But the goal that we set out for
was that for most of the people,
00:01:58.006 --> 00:01:59.506 A:middle
most of the users, most
00:01:59.506 --> 00:02:03.396 A:middle
of the time their battery would
last all day, they would plug it
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:01:59.506 --> 00:02:03.396 A:middle
of the time their battery would
last all day, they would plug it
00:02:03.396 --> 00:02:04.856 A:middle
in at night and that was it.
00:02:05.726 --> 00:02:08.376 A:middle
Now, we know that
that's a game changer
00:02:08.556 --> 00:02:11.806 A:middle
because of our experience
with products like iPad,
00:02:11.806 --> 00:02:16.886 A:middle
where that's the usual behavior
and once you get to that sort
00:02:16.886 --> 00:02:20.676 A:middle
of threshold, life gets a lot
better, there's a lot of bang
00:02:20.676 --> 00:02:23.336 A:middle
for the buck in getting
to that point.
00:02:27.766 --> 00:02:30.086 A:middle
Now, our latest products
which I'll go
00:02:30.086 --> 00:02:32.406 A:middle
into some more detail we
think we've gotten there
00:02:32.406 --> 00:02:33.876 A:middle
through a number of techniques.
00:02:33.876 --> 00:02:36.456 A:middle
It wasn't easy but
it was a lot of fun
00:02:36.456 --> 00:02:40.526 A:middle
over the development really with
a laser focus on battery life,
00:02:40.526 --> 00:02:43.766 A:middle
kind of a new perspective
in how you develop apps.
00:02:43.766 --> 00:02:47.196 A:middle
I hope to sort of translate
some of that to you or to--
00:02:47.456 --> 00:02:50.886 A:middle
I imbibe you with that because
in fact application developers
00:02:50.886 --> 00:02:54.536 A:middle
have a huge impact on the
user's battery life as well.
00:02:55.326 --> 00:02:59.176 A:middle
So, here we have a typical
customer out at the beach,
00:02:59.246 --> 00:03:03.986 A:middle
they've got the-- I don't
know if this is Mavericks,
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:02:59.246 --> 00:03:03.986 A:middle
they've got the-- I don't
know if this is Mavericks,
00:03:04.056 --> 00:03:07.236 A:middle
probably isn't Mavericks
but here's a surfer who is,
00:03:07.236 --> 00:03:11.066 A:middle
you know, in between
surfing is editing his movies
00:03:11.066 --> 00:03:12.076 A:middle
with Final Cut Pro.
00:03:12.566 --> 00:03:18.096 A:middle
Well, even in this case assuming
he spends a reasonably long time
00:03:18.096 --> 00:03:20.496 A:middle
surfing even with
a heavy duty app
00:03:20.496 --> 00:03:24.196 A:middle
like Final Cut Pro he may
experience all-day battery life.
00:03:24.636 --> 00:03:26.896 A:middle
Users do not use our computers--
00:03:26.996 --> 00:03:29.146 A:middle
do not use their
computers continuously
00:03:29.456 --> 00:03:31.856 A:middle
and you can give them that
experience of only plugging
00:03:31.856 --> 00:03:35.196 A:middle
in at night in just a wide
variety of situations.
00:03:36.216 --> 00:03:40.506 A:middle
Now, with the latest MacBook
Airs combination of the hardware
00:03:40.506 --> 00:03:45.116 A:middle
and the latest MacBook Airs
that has well ULT processors
00:03:45.346 --> 00:03:46.376 A:middle
which are very efficient,
00:03:46.936 --> 00:03:52.616 A:middle
and Mac OS X Mavericks we think
we have reached that threshold
00:03:52.906 --> 00:03:54.736 A:middle
where people can
start to not think
00:03:54.736 --> 00:03:56.446 A:middle
about their battery
during the day
00:03:56.446 --> 00:03:59.176 A:middle
and we think there's
incredible value to that.
00:03:59.386 --> 00:04:02.246 A:middle
Now, I'll go into some
detail on how we get there,
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:03:59.386 --> 00:04:02.246 A:middle
Now, I'll go into some
detail on how we get there,
00:04:02.656 --> 00:04:06.496 A:middle
it's actually there's a
lot of ingredients that go
00:04:06.496 --> 00:04:08.876 A:middle
into giving the customers
a great battery life.
00:04:09.156 --> 00:04:14.446 A:middle
Starting with chemistry, the
chemistry in the battery,
00:04:14.976 --> 00:04:18.125 A:middle
now we're used to Moore's law
00:04:18.125 --> 00:04:21.536 A:middle
with silicon wherever 18
months things get twice as--
00:04:21.956 --> 00:04:23.636 A:middle
you have twice as
much compute power,
00:04:24.016 --> 00:04:25.786 A:middle
that's not the case
with chemistry.
00:04:26.276 --> 00:04:28.996 A:middle
With batteries, batteries
have been slowly
00:04:28.996 --> 00:04:30.606 A:middle
but surely getting
better over the year
00:04:30.606 --> 00:04:33.976 A:middle
but the gains are measured in
single digit percentage points.
00:04:34.536 --> 00:04:40.686 A:middle
Nonetheless, Apple's been paying
a tremendous amount of attention
00:04:41.096 --> 00:04:44.056 A:middle
to battery life technology
and battery chemistry
00:04:44.216 --> 00:04:46.116 A:middle
and we have gotten
gradually better.
00:04:46.116 --> 00:04:48.796 A:middle
So, this is one of the
ingredients in getting there
00:04:49.036 --> 00:04:50.706 A:middle
in terms of all-day
battery life.
00:04:52.296 --> 00:04:55.906 A:middle
Second area though, the
hardware itself the silicon,
00:04:56.416 --> 00:05:01.336 A:middle
both at the atomic scale, the
nanoscale and the architecture
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:04:56.416 --> 00:05:01.336 A:middle
both at the atomic scale, the
nanoscale and the architecture
00:05:01.336 --> 00:05:05.506 A:middle
of the chip itself, that's
extremely important at getting
00:05:05.506 --> 00:05:06.506 A:middle
to all-day battery life.
00:05:06.506 --> 00:05:08.816 A:middle
I'll go into that
in some detail.
00:05:09.446 --> 00:05:12.146 A:middle
Of course the system
software is responsible
00:05:12.146 --> 00:05:15.976 A:middle
for scheduling the CPU
and other resources
00:05:16.226 --> 00:05:20.776 A:middle
in the way that's most energy
efficient and we've done a lot,
00:05:20.776 --> 00:05:24.106 A:middle
this is where we've done a lot
of work in Mac OS X Mavericks
00:05:24.256 --> 00:05:26.976 A:middle
to make sure that things
are as efficiently scheduled
00:05:26.976 --> 00:05:31.216 A:middle
as possible that the energy
is being spent on work
00:05:31.216 --> 00:05:34.496 A:middle
that the user actually
wants done versus work
00:05:34.686 --> 00:05:37.286 A:middle
that maybe they don't
care about.
00:05:37.286 --> 00:05:39.446 A:middle
So, we'll go into a
lot more detail on that
00:05:39.446 --> 00:05:41.096 A:middle
and actually a lot
of sessions further
00:05:41.096 --> 00:05:42.936 A:middle
on during the week
we're going to focus
00:05:42.936 --> 00:05:44.296 A:middle
on that sort of thing as well.
00:05:44.296 --> 00:05:47.926 A:middle
And then finally, as I mentioned
you the application developer
00:05:47.926 --> 00:05:49.376 A:middle
are part of the equation here.
00:05:49.746 --> 00:05:54.176 A:middle
And it's important for you to
use the tools that are provided
00:05:54.176 --> 00:05:57.116 A:middle
in Mac OS X Mavericks to
take, take a microscope,
00:05:57.116 --> 00:06:00.346 A:middle
take a closer look at how your
application is using energy
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:05:57.116 --> 00:06:00.346 A:middle
take a closer look at how your
application is using energy
00:06:00.796 --> 00:06:06.196 A:middle
and try and maximize the
efficiency to give that customer
00:06:06.336 --> 00:06:08.886 A:middle
that all-day battery life
that they really want.
00:06:09.716 --> 00:06:15.436 A:middle
Now, Apple is, as a company,
uniquely positioned compared
00:06:15.436 --> 00:06:17.916 A:middle
to a lot of others being
at the intersection
00:06:17.916 --> 00:06:19.246 A:middle
of hardware and software.
00:06:19.516 --> 00:06:23.176 A:middle
We build hardware and we build
the software that goes with it.
00:06:23.376 --> 00:06:26.756 A:middle
The system software so we can
spend a lot of time making sure
00:06:26.756 --> 00:06:29.646 A:middle
that those two things
are optimized together
00:06:29.646 --> 00:06:33.516 A:middle
and play well together to give
maximum battery life possible.
00:06:34.176 --> 00:06:36.826 A:middle
And that's what I want to
spend some time talking about.
00:06:37.186 --> 00:06:40.856 A:middle
How the hardware plus the
software working together
00:06:41.396 --> 00:06:42.906 A:middle
maximizes battery life.
00:06:43.556 --> 00:06:47.496 A:middle
Now, silicon itself
has come along way
00:06:47.496 --> 00:06:48.666 A:middle
in the last thirty years.
00:06:48.896 --> 00:06:52.706 A:middle
So, this is actually
on your left.
00:06:52.706 --> 00:06:57.076 A:middle
The original 68K, the
68,000 processors that went
00:06:57.076 --> 00:07:01.396 A:middle
into the Mac 128K and
Mac 512 back in 1984.
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:181083,LOCAL:00:00:00.000
00:06:57.076 --> 00:07:01.396 A:middle
into the Mac 128K and
Mac 512 back in 1984.
00:07:01.896 --> 00:07:08.506 A:middle
Now, that chip had oddly enough,
around 68,000 transistors on it.
00:07:09.326 --> 00:07:13.266 A:middle
The Intel Core i7, the
fourth-generation Core i7
00:07:13.266 --> 00:07:15.896 A:middle
that we have in the
MacBook Air has
00:07:15.896 --> 00:07:19.546 A:middle
about 1.4 billion
transistors on it.
00:07:19.976 --> 00:07:23.366 A:middle
Now, you know, the transistors
00:07:23.366 --> 00:07:26.656 A:middle
in the original Mac we're
not all that efficient.
00:07:26.656 --> 00:07:30.496 A:middle
In fact, if they drew the
same, if the transistors
00:07:30.496 --> 00:07:33.136 A:middle
in the Core i7 were drawing
the same amount of power
00:07:33.136 --> 00:07:37.486 A:middle
as the transistors in the 68K,
then the amount of power needed
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to run the Core i7 would be
equivalent to the power drawn
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by about 10 US average
households about 20,000 kilowatt
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or 20,000-- 20 kilowatts.
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Obviously, you know, a lot
has gone into making sure
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that that catastrophe doesn't
happen, one of the things is
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of course the transistors
just got smaller but again,
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of course the transistors
just got smaller but again,
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this chip is running
at a higher frequency
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and thus using more power
just because of that.
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So, a lot of work had
to go in to the physics
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of the transistors in order
to make them more efficient.
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I want to talk a little
bit about some of those.
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So, Intel in starting
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at the early 2000 began using
something called strained
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silicon, not just normal
silicon but strained silicon.
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Strained silicon actually
has germanium atoms inserted
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in between the silicon atoms and
the net result of that is that--
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is that they can run
at a lower voltage.
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The voltage gap is
lower and running
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at a lower voltage
has a big effect.
00:08:46.466 --> 00:08:49.426 A:middle
Energy draw tends to be
proportional to voltage squared
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so anything you can do
to reduce the voltage
00:08:52.306 --> 00:08:55.866 A:middle
and still switch those
transistors has a big effect.
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So, Intel put a lot of effort
into moving to strained silicon.
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But that wasn't enough.
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These things went forward.
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Another problem arose which
was that between the gate
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and the channel in
this transistors,
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there's an insulator,
silicon dioxide.
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Well that silicon dioxide as the
transistor shrunk was getting
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to be just a few atoms thick.
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And as a result electrons
actually tunnel through there,
00:09:21.176 --> 00:09:22.466 A:middle
they're leaking through there
00:09:22.586 --> 00:09:25.196 A:middle
and that leakage is
simply wasted energy.
00:09:25.526 --> 00:09:29.296 A:middle
There's R-squared energy leaked,
being wasted in that case.
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So, what Intel did is they
looked around and they said,
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"Is there any way we can make
those gates a little thicker
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but still get the
same capacity."
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And that's where they came
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up with what's called
high-k metal gates.
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And that those start
being used in 2007.
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That was a big breakthrough
because you could get rid
00:09:45.076 --> 00:09:46.726 A:middle
of that leakage that would--
00:09:46.726 --> 00:09:49.616 A:middle
was really sitting there
continually drawing
00:09:49.616 --> 00:09:53.686 A:middle
down your battery and they
used a material called hafnium,
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hafnium oxide which oxides
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which have a very high
dielectric constant
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so you can increase the
thickness of the gate.
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so you can increase the
thickness of the gate.
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And then finally,
most recently in 2011,
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they came up with something
00:10:05.186 --> 00:10:07.346 A:middle
that I guess they're marketing
guys called it Tri-gate
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but it's really a
three-dimensional structure
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for the gate so that
the gate can actually be
00:10:12.816 --> 00:10:16.406 A:middle
on all three sides of the
channel of the transistor rather
00:10:16.406 --> 00:10:18.546 A:middle
than just a plate on the
top of the transistor.
00:10:18.826 --> 00:10:21.666 A:middle
And these transistors are much
more efficient maybe 50 percent
00:10:21.666 --> 00:10:22.246 A:middle
more efficient.
00:10:22.706 --> 00:10:24.966 A:middle
So, there's going to be
more things in the future
00:10:24.966 --> 00:10:27.736 A:middle
but you can tell even--
even at the nanoscale,
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a lot of stuff is being done to
make these chips more efficient.
00:10:31.976 --> 00:10:34.346 A:middle
Now, what's the result?
00:10:34.346 --> 00:10:40.246 A:middle
The result is that on the latest
chips, we're talking nanojoules
00:10:40.246 --> 00:10:42.476 A:middle
or tens of nanojouels
per instruction.
00:10:42.836 --> 00:10:43.786 A:middle
So, what's a nanojoule?
00:10:43.786 --> 00:10:47.686 A:middle
So, a nanojoules is a billionth
of a joule and a joule,
00:10:47.686 --> 00:10:51.726 A:middle
a billionth of a joule is a
very tiny amount of power.
00:10:52.026 --> 00:10:56.776 A:middle
I like to think sometimes in
terms of biology and in fact
00:10:57.046 --> 00:11:00.806 A:middle
when a neuron fires in your
brain its taking on the order
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when a neuron fires in your
brain its taking on the order
00:11:00.806 --> 00:11:03.516 A:middle
of picojoules, about a
thousand times as much.
00:11:03.516 --> 00:11:07.156 A:middle
So, you can sort of think
of an instruction executing
00:11:07.156 --> 00:11:11.206 A:middle
in the Core i7 as being
same amount of power,
00:11:11.206 --> 00:11:15.906 A:middle
same amount of energy is
about several thousand neurons
00:11:16.246 --> 00:11:19.166 A:middle
in your brain firing, so your
brain executing one instruction.
00:11:19.566 --> 00:11:22.136 A:middle
So, we're really getting
down there to the level
00:11:22.136 --> 00:11:25.796 A:middle
where biological systems have
evolved over obviously billions
00:11:25.796 --> 00:11:26.826 A:middle
and billions of years.
00:11:27.896 --> 00:11:35.286 A:middle
Now, this is a micrograph of the
Haswell ULT chip from Intel and,
00:11:35.546 --> 00:11:39.596 A:middle
you know, it's a small chip
about the size of a fingernail
00:11:39.986 --> 00:11:42.936 A:middle
but on here are 1.4
billion transistors.
00:11:42.936 --> 00:11:46.076 A:middle
And that's divided up into
the functional units the--
00:11:46.426 --> 00:11:48.406 A:middle
in this chip there
are two cores.
00:11:49.316 --> 00:11:52.606 A:middle
There is a huge amount as
Phil said yesterday devoted
00:11:52.606 --> 00:11:55.826 A:middle
to the GPU to the
graphics processor.
00:11:56.456 --> 00:12:00.576 A:middle
There's the shared L2 cache,
the memory manager and some
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There's the shared L2 cache,
the memory manager and some
00:12:00.576 --> 00:12:02.556 A:middle
of the things for managing DMA.
00:12:02.926 --> 00:12:06.676 A:middle
Now, the interesting thing
about modern chips is
00:12:06.676 --> 00:12:11.766 A:middle
that during execution, you can
power down parts of those chips
00:12:11.766 --> 00:12:12.826 A:middle
that aren't being used.
00:12:13.016 --> 00:12:15.356 A:middle
If you're not using the GPU
right now, you can turn off
00:12:15.356 --> 00:12:17.246 A:middle
that part of the
chip, saving energy.
00:12:17.826 --> 00:12:19.366 A:middle
If you're not using both cores,
00:12:19.366 --> 00:12:20.716 A:middle
you can turn off
one of the cores.
00:12:20.816 --> 00:12:22.796 A:middle
You're not using both
cores, turn those off.
00:12:23.296 --> 00:12:26.486 A:middle
And that turns out to
be architecturally one
00:12:26.486 --> 00:12:28.576 A:middle
of the key ways to save power
00:12:28.576 --> 00:12:31.286 A:middle
in these portable systems
that we have today.
00:12:31.756 --> 00:12:34.116 A:middle
Now, it requires
close interaction
00:12:34.116 --> 00:12:37.116 A:middle
between a system software and
the silicon in order to make
00:12:37.116 --> 00:12:41.236 A:middle
that happen correctly
but as we'll get into,
00:12:41.236 --> 00:12:43.746 A:middle
if you do it right, you can
save a huge amount of power.
00:12:44.316 --> 00:12:48.486 A:middle
Now, this shows you what that
looks like and in reality,
00:12:48.486 --> 00:12:51.056 A:middle
this is actually,
it's not Haswell,
00:12:51.056 --> 00:12:52.866 A:middle
it's Ivy Bridge previous
generation
00:12:53.226 --> 00:12:57.416 A:middle
but it's what called an
infrared emission microscopy.
00:12:57.786 --> 00:12:59.336 A:middle
So, you're looking actually
00:12:59.336 --> 00:13:02.886 A:middle
at the heat waves coming off
the chip as its executing.
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at the heat waves coming off
the chip as its executing.
00:13:03.466 --> 00:13:06.696 A:middle
So, the blue spots
are cooler, the orange