Advanced CPU Designs: Crash Course Computer Science #9

[@srpilha]

Every episode I watch of this series has me going "well THAT is f*cking impressive, everyone who came up with these ideas is a bloody genius". I love it. :)

[@uHnodnarB]

"No word on whether it will run Crysis yet, but I suspect it might." This is one of my favorite series yet!

[@acousticpsychosis]

That gave me a very hearty chuckle.

[@ThZuao]

A 10 year old meme...

[@syvarris467]

RIP every supercomputer yet. Crytek OP

[@ganaraminukshuk0]

Brandon Hu All you need is an RGB LED light strip. That ought to help.

[@tallblondekid]

Probably can't run crisis at all, since each core is only clocked at about 1.4 GHz

[@RaidenFreeman]

Two semesters in 12 minutes. That's efficiency.

[@thomasdamours7325]

I like to think of cache as an ability similar to being able to borrow several books at once from the library: For a fast reader, this means being able to read more books without having to take the bus to go to the library again. The reader may not be able or interested in reading all the books they end up borrowing, but overall, it still increases quite a bit their ability to read more books in a shorter period of time.

[@박정민-o4n6r]

연구에서 매일같이 컴퓨터로 데이터처리를 하고, 실험장비를 컨트롤하는데 컴퓨터에 대해 너무 모르는 것 같아 퇴근길에 듣기 시작했습니다. 너무 유익한 시리즈에요! 앞으로도 좋은 영상 많이 부탁드립니다.

[@pushbaner5219]

crashcourse/pbs deserves to run for decades to come...its one of the best parts about youtube....

[@midnightrizer]

been on you tube for the last 6 months there is more to the net and you tube that cats ya?

[@JimPlaysGames]

In Star Trek, Data says he can perform 60 trillion operations per second. That Chinese supercomputer outperforms a 24th century android by orders of magnitude. The speed of computer advancement again outpaces science fiction.

[@jasonz8635]

It was made in 1989, what do you expect?

[@tylerboothman8060]

JimPlaysGames _Maybe he was on sale at Walmart.

[@john11719]

Them to use Moore's law to figure out what would be more accurate.

[@unvergebeneid]

It's not all about clock speed ;)

[@SotraEngine4]

Well, there is a limit to how small transistors can possibly get. Data also moves around, so he got to have motors and stuff inside. So maybe it's what is possible to get at that size?

[@anandananda2277]

Never trust a computer you can't throw out a window. ~Steve Wozniak

[@KingsleyIII]

Never trust an atom. They make up everything!

[@fission1110]

At least everything that's matter anyway

[@jasondads9509]

everything that matters*

[@fission1110]

jason dads that's the joke :p

[@marcelkruger5187]

Although both are technically, Jason's works better if you say it out loud.

[@lpfcdd]

This is again proving the point.... some people needs visuals to understand the concept and not only the abstract logic. I struggled with Geometry for the same reason in my school life .... thanks to this series , I can finally visually see all the 5 years of computer studies I did ...... Thanks once again !!!!!!!!!!!!

[@BlueyMcPhluey]

by far the best crash course series, please keep going forever :)

[@user-nj1qc7uc9c]

int epNumber = 9; while (true) { CarryAnne.MakeCrashCourseEp(epNumber); }

[@neelimgoswami6336]

@@user-nj1qc7uc9c you forgot epnumber++;

[@mohaamer6866]

this show started good but now it blows my mind every week. Good job Crash Course

[@emanonmax]

By the way: Branch prediction is also the cause of the current major security problem. Because what if the conditional jump is the condition that checks for if the program has the right to access some memory? (By the way: in my student accommodation we have a dryer that can dry completely in about 40mins)

[@imranariffin2688]

Caching, pipelining, predictive execution, superscalar, multicores--wow everything in a concise 1 episode. That's amazing! Really looking forward to the next ones!

[@mattvw9287]

This is my favorite Crash Course series yet. Film history in a close second. Great job on development.

[@Garrison86]

I have just completed my Computer Engineering Technology program, I have referred back to the entire Computer Science playlist on crashcourse, and it has helped me so much, great series.

[@fishmonger1526]

I really enjoy the crash course videos - I tend to put them on and fall asleep to different playlists every night. I'm glad they now have one on computing, bravo! Thank you John, Hank, PBS and everyone involved for continuing this series. *Not that I "fall asleep" cause they are boring, but IMO they are very tranquil and relaxing to watch.

[@admc8]

Fishmonger ! Glad to hear I'm not the only one!

[@ohjajaja]

The only reason I kept studying this stuff was because of things like MIPS, FLOPS and Dirty Bits. Computer Science is filled with funny and weird names.

[@NotExplosive]

We also developed a weird vocabulary that lead us to say things like: "When the parent dies, kill all the children"

[@zapp1984]

But then who gets the inheritance?

[@LostInNumbers]

West Coast Photograpy Zombies are the reason why need to kill all the children.

[@Stormaes]

I really like the terms BogoMIPS and BogoSort because they are fun to say and because if you suggest that someone BogoSort a list only the programmers laugh. The hexspeak "Magic Debug Values" are also pretty funny, eg. the C00010FF value is used to indicate an iOS app that was killed because of a thermal event.

[@IceMetalPunk]

+Stormaes My favorite type of sorting is the Quantum Bogosort. It's super advanced!

[@cassidymalott225]

I love how information packed this is but if I zone out for 15 seconds I've already missed an entire topic 😭

[@EugeneKhutoryansky]

Do you actually use that ancient looking oscilloscope in the background?

[@humanity3.090]

I am NEVER disappointed after watching a CC video, and this was no exception!

[@RicardoDelfinGarcia]

In the comments to find dryer recommendations. No one has mentioned anything :'(

[@MetaBloxer]

I have dryers in my dorm that dry in 60 minutes. I don't know what brand they are, and they are commercial dryers, but I can tell you later.

[@JimboPalmer]

I have an Electrolux with a 15 minute drying time for small loads, large loads take 49 minutes. www.electroluxappliances.com/Washers-Dryers/Washing-Machines/Dryers/EFMG617STT/

[@PaulHojda]

The dryer in my apartment complex can dry a load full of clothes in half an hour at medium heat no problem. It is quite big though, not something you'll be able to buy privately, I don't think. It's a Nortec

[@TiberiusStorm]

Our old Kenmore dryer will dry a load of laundry in 40 mins!

[@midnightrizer]

which is really a maytag Kenmore was Sears in house branding :)

[@josemunguia5660]

As a computer science student. This series of videos illustrate all the theory I have studied. Thank you!

[@mfaizsyahmi]

"SPECULATIVE EXECUTION" No wonder KZbin is now suggesting this video to me in January 2018, after the Meltdown & Spectre bugs were let known...

[@sk8erbyern]

@Oz jak The bugs are directly related to SPECULATIVE EXECUTION and of course they were known

[@IStMl]

not bugs

[@asdfasdfadfasdf2979]

This video made me sad. 10 years ago i spent 2 years in an ICT highschool course, but this playlist up to this point has thought me more already. The only thing i remember learning there was that you could power off a pc quicker by just pulling out the plug, followed by the students explaining to the teacher what bad sectors are. Those years killed nearly all my enthusiasm for ICT, as did my internships in refurbishment companies.(although they were fun) At this point through this playlist i notice that things aren't so obvious anymore and i have to rewind here and there to fully grasps the concepts, and i realized... this stuff is still really exciting!

[@AuburnKamstra]

I took 800 words of notes on a 12 minute video, your communication has a very high level of efficiency

[@neutronstar6739]

I wish this series existed back when I was 13..I was super curious on how computer work and stuff.

[@mxthunder2]

really falling in love with this series! awesome stuff! been in the industry for years now and this takes me back to my college years. love the fundamentals.

[@iluan_]

Watching this videos as I start my journey into digital design and fpga development is kinda cool. I love how intuitively they explain things that took me a while to learn, and that I'm struggling to apply.

[@arooobine]

Q: What did the data say to the CPU when the cache got full? A: "Cache me ousside how bow dah!" Q: What did the paraplegic program with a stutter say to the CPU pipeline? A: "Help I've been parallelized!" Q: Why was the dependent instruction executed in front of the others? A: For protesting the pipeline and causing delays! Q: Why did the instructions eventually rise up against the CPU? A: They were being executed based on speculation. Q: What is the most famous speech ever given by a cache after being cleared? A: "4 cores and 7 clears ago..." Q: Why were the corny CPU jokes banned from KZbin? A: Too many FLOPS!

[@jasonz8635]

Q: Why did Hersheys not succeed? A: He was executed becuase of Hearshey.

[@camerongray7767]

Dude u are so fun y

[@camerongray7767]

Hello me from 7 months ago!

[@QuasiELVIS]

I feel pain while reading those jokes.

[@StarDoesntUpload]

This is gold.

[@paulosullivan3472]

Love this series I think you guys are doing a great job simplifying some complex concepts for people. Thanks for all the hard work!

[@EvilSapphireR]

The series we don't deserve, but absolutely one that we needed!

[@rikschaaf]

The techniques that were shown in this video are very relevant to the recent Spectre issues with pc's: cache misses and branch prediction.

[@helenas5550]

Carrie Anne is absolute delight and seems to be more comfortable in front of the camera every week. I'm learning so much. Please do more technical series with her! And, you know, the rest of computer science please.

[@shawndokken9427]

if your DRYER takes 90 mins, you must have a BLOCKAGE IN YOUR VENTING to the outside. the pipes often fill with lint and blocks airflow. if left unchecked, it could cause a FIRE. there are cleaning tools for this or you could take the vent tubes apart and clean them by hand. btw. this series is awesome!

[@BlakeEdwards333]

This video went through and touched upon four of my computer science classes thus far. This is a great video to review CPU architecture and instruction execution methodologies! Thank you so much!

[@balajisundarrajan9684]

This graphics team is one of the best I have seen in YT

[@grev.]

so far this has been an excellent distillation of computer engineering for computer scientists. i remember taking this class in junior year of a CS major and it was by far the most interesting and informative class I ever took.

[@Chelnaka]

Irony. Carrie Ann talks about "speculative execution", which (for those watching in 2018 and are unaware of the malware's MO) is what Meltdown and Specter exploited. That's the reason why you never say any tech/science thing is impossible. You never know what people might figure out.

[@thomasgeorge237]

I've not been a PC gamer now for 10 years or so... but hell, even I got "No word on whether it will run Crysis yet, but I suspect it might." .... and had a good chuckle. Really enjoyed this one. I graduated (Comp Sci) in 1998. The run down on the various techniques to improve CPU design was a great nostalgia trip for the last 20~23 years... reading about it in magazines, then later in uni, and then on the internet.

[@nachannachle2706]

As a programmer, I'm loving this series to the moon and back.

[@CoryMck]

*"Dirty Bit"* _Wow, the Black Eyed Peas really were ahead of their time._

[@DylRicho]

Or at least 10 years behind.

[@mustafayldrm3449]

Woa, you just summarized most of a Computer Organization book that I read some time ago. Not too shallow, not too technical. Incredible video for people who wanna remember one thing or two.

[@PTNLemay]

I'm a bit surprised that the mythology course ended up being more popular than this one. Not to diss it or anything, just surprised me. Though, I am a huge engineering and tech nerd, so maybe I'm biased towards this computery stuff.

[@imperator9343]

Well to start with, there's still a pretty hefty gender gap that is probably holding this particular series back a decent amount. A lot of girls and women simply aren't interested in Computer Science compared to the number of guys that are, and I doubt there is nearly as significant of a gender disparity regarding mythology.

[@avalencia9628]

I do understand you, personallym Computer Science and World History are my favorites But being honest, CS might be a little more complicated to understand, and that's probably why Mythology is a bit more popular Because, I mean, come on, Gods have really cool stories and everyone is fascinated by at least one Greek story

[@wanderingrandomer]

Not to say that this isn't interesting, but Computer Science regularly makes my brain explode, whereas mythology is pretty easy to follow.

[@primordial.sounds]

Mythology = Easy answers that happen to be mostly false. Computer Science = Real answers that take a lot of processing!

[@magical11]

That's like saying: History = real answers that are mostly true; Computer science = real answers that are mostly boring! Mythologies are easier/more popular because they are retold as stories. They have a narrative and a human connection that's been repeated over millennia. Compared to computer science, which usually is impossible to relate to the human experience, mythology is far easier to digest and enjoy.

[@FedJimSmith]

Excited for next week's episode... but I wish there's more about hardware.

[@IceMetalPunk]

Most of this series, and most of this video, has been about hardware architecture...

[@FedJimSmith]

what I'm hoping about is that they bring insight of how various hardware works like 3d printer, computer monitor, etc..

[@armorsmith43]

FedJimSmith she runs a channel called GeekGurlDiaries that does hardware stuff.

[@dougmhd2006]

"Dirty bit",...not to be confused with, under any circumstances whatsoever, with "naughty bit". :D

[@sagarshah1905]

Loved this crash course series ! Gave me clarity on how computer works ! Thank you so much !

[@dilipdas5777]

Best channel for knowing fundamental of computer science

[@JacobHorwath]

Interesting that this video, which covers out-of-order execution and speculative execution, was released in April. Whereas, the Spectre and Meltdown vulnerabilities (relating to those features) were "discovered" by 4 separate research teams within 3 months of the release of this video. I wonder if one of those people watched it!

[@franckndame8921]

Thanks!

[@6san6sei6]

i am in love with this course ! Thanks !

[@chillsahoy2640]

Parallelizing is a real strategy? Interesting! I've always done this without even thinking about it whenever I have had to do consecutive, simple tasks at home or at work. While waiting for "process 2" to finish, you might as well get started on "process 1" for the next batch, then go back to finish off "process 2".

[@DaniloSilva-pl3sq]

IBM's supercomputer Summit overtook Sunway Taihulight, becoming the world's fastest supercomputer

[@jiri-one]

Amazing video, this should be spread throughout the education system worldwide.

[@olivierkoster]

crashcourse is literally helping me pass uni

[@loungelizard836]

Excellent well-presented, clear. First time I feel like i really understand the cache and pipeline concepts!

[@NeonThoughtBox]

Nothing can play Crisis at max settings. I don't think anyone even knows how they developed the game. O_o

[@jasonz8635]

They didn't develop the game, a time traveler gave them a copy of the game in the year 1930. Where do you think we got our computers from?

[@dalmationblack]

Time travel.

[@NeonThoughtBox]

I don't know about you, but all of mine come from Japan and Singapore. lol

[@NeonThoughtBox]

Yes indeed. It only took 3 years after the release of Crysis 3 to get a good cpu/gpu combo to run it. lol

[@Boryspitzanzx]

This means it just has poor optimization. You could set up a game that runs on path tracer and all you will get is a a blurry, noisy mess every 1/60 or 1/30 of a second

[@michaslezak9397]

Thank you a lot! That series is a real treasure!

[@spencerwhite3400]

I mean, the supercomputer feels like the most amazing thing ever, but when IBM used to fill an entire room with vacuum tubes, it probably felt like the most incredible thing ever.

[@EscapeMCP]

Bosch dryers are good. 50 mins dry time on low. I never use high, but I guess 30 mins would be within the realms of possibility. The drying time is going to highly depend on your spin speed of your washing machine though, so maybe you need a new waching machine?!?

[@conway642]

EscapeMCP bro mine, when set to normal is like 28 mins

[@theeverythingplace672]

why is she talking at 2.5 GHz?

[@NicolaiCzempin]

Do you not run an optimised input decoder? ;-)

[@Feedback_Jack]

Being able to say "Dirty bit" repeatedly without giggling is the sign of a true professional. (pfft, dirty bit *giggles*)

[@TheDeadEyeSamurai]

"If anybody says he can think and speak about quantum theory without getting giddy it merely shows that he hasn’t understood the first thing about it! " - Niels Bohr

[@thambithurai4115]

Cool video, covering many topics on processors!

[@JohnRaschedian]

Nice job Carrie Anne and the whole PBS team!

[@Scerttle]

This and Crash Course Mythology are magnificent.

[@JM-jk9vz]

This whole series has been great help. Thank you so much.

[@PendragonDaGreat]

It was only a matter of time till we got a "But will it run Crysis?" joke. I gave a solid guffaw. Well played.

[@crazyphil7782]

There's one thing I really couldn't get my head around when I was a student. How in the heck do they manage to attain GHz frequencies with a oscillators limited to a couple dozen megahertz? PLL's are such a genius invention

[@zakariabahbaz5348]

Did anyone else's heart fall when they saw the bent CPU prongs at 0:36?

[@casper6060]

Funny, this video kinda explains some of the Spectre & Meltdown error :)

[@catherinebyerly8334]

Real talk on the dryer thing: Usually long dry times actually come from your ventilation out of the back of the dryer to the outside. That hose and the pipe between the hose connection and the side of the building get clogged with lint and the occasional wasp nest. Cleaning those out will shave tons of time off your dryer and save your money on your electric bill.

[@BosonCollider]

I was a bit hesitating when I started watching this series, but now I feel that it's probably the best one on this channel so far tbh. P.S: Will you also mention virtual memory and paging at some point?

[@NickKonev]

Just an awesome series, recommend it to everyone

[@0xOrganix]

Top of the line videos , you rock

[@sofialpaca2563]

I had a uni professor that used hundreds of paralellized ps3 to do encryption work... as a publicly founded research. When they stopped it, he gave away the consoles to students, and this caused ENTIRE classes to get empty because people were getting in line to fetch some. He's an absolute legend.

[@Collinoeight]

Branch Prediction? This sounds like a great idea! I'm certain that nothing bad will ever come of implementing that in everything!

[@rohitpawar3568]

Thank you for making this brilliant and easy to understand series!!!!!!!! 😁

[@CynicatPro]

Loving this series! keep up the awesome!

[@cpvp20]

THIS COURSE IS AMAZING

[@tonhu100]

Will you talk about RISC and CISC differences? I love this great series, thanks =D

[@lemonade2473]

So Cache is your kitchen counter top, RAM is your fridge, and hard drive is your grocery store.

[@TheGerm24]

I remember the washer/dryer sequencing analogy from my college computer science courses. I guess it is a favorite.

[@blodstainer]

It might be worth noting that branch prediction is part of the security problem with Spectre and Meltdown

[@FayenMorval]

SOOOO COOOL. My college classes can't explain it like this.

[@123firemasterr]

This is a really nice series

[@thtcaribbeanguy]

i cant wait for programming.....(as a programmer myself) this is such a nice refresher course

[@xhappybunnyx]

Ok 8:53 is officially when the "computers are magic" started creeping back in. How the heck do computers predict which brances will be executed?? Ok now that I think about it, they're designed to execute this stuff, but how does it scout ahead without just executing it in the first place? Guess I've got some googling to do

[@vincybadman871]

I love you, you're so enthusiastic about this topic you can see it in your face, makes me want to watch. My favorite host after the Greene brothers.

[@elziolima8014]

Thanks for subtitles!! :)

[@addisbyte2279]

WOW never learn so much pls keep it up. I wish there were more simulation like in logism...

[@deldrinov]

yay 1800X!

[@rjfaber1991]

Yay indeed! I'm loving mine so far...

[@TheChronichalt]

3950x incoming!!! 7nm here we go! I have a 2700x

[@thermonuclearcat5419]

Great episode! Many thanks for making this series

[@dimi-eu]

Overall 7/10 :-) I really think this series can have impact on different age groups, and not only people with tech background or motivation. And that would be great! But I also have some critics, hope a useful feedback: *A. Host is talking far too fast.* *B. Not all technical facts are correct.* Example - The reason for few MB of cache is not the SIZE of the DIE. Is the COST of the SRAM, i.e the cost of CACHE memory. Back in time, when we speak of KB, again COST was the biggest obstacle and first factor regarding CACHE Size. Manufacturing process changed, so die size could've been scaled, but it was not reasonable to do so. Already having the SRAM cost to the roof, leaves nothing for other expenses in the pursue of bigger Cache size and perf boost. So the barrier was and still is COST of SRAM. Nowadays you have CPU & GPU on the same DIE, so the die size is not the main factor today, was not a factor back then. Hope that's clear. I think this is one of the straightforward examples of wrong information. Hope this feedback will be taken into consideration, because these series have good potential. For fluent or advancement speaker sure it's no problem the pace of the presenter, it's rather engaging. But for the bigger audience of non-native speakers... most definitely a big loss of audience. And probably that same audience, group of people, will not even going to try to see another video from the series. That would be a loss for the series in my opinion. As well and for those people came to seek information or just watch a cool informative video , which to be honest is even more of a reason to reconsider the pace. KUDOS for the effort and outcome. The video is way above average videos on youtube regarding tech, but has big room for improvements too ;-)

[@angelcollina]

About dryers: I had a Bosch dryer that had a moisture sensor and I routinely dried permanent press type clothes (dress shirts, slacks, etc.) in about 15 mins. I think it was one of those energy efficient ones.

[@Incestbarnet1337]

This series is so good!

[@arthurabraham3271]

11:22 "no word on if it can run Crysis" -Carrie ann u r awesome

[@SexyBakanishi]

The only key thing you guys haven't talked about is how you get these things in and out of the cpu. Like with old computers how do you put instructions in and how do you get the calculations read to memory out? Like before computers had screens and also now that they have screens how does the data get to display?

[@shizukuchan6541]

Amy G we had punched cards for the really prehistoric primitive computers. I think she just touched upon these topics in the first few videos.

[@VinayYadav-bt4yd]

Going good ,,,,keep uploading helpful videos ,,, Greetings from India

[@danielweatherly9733]

Awesome awesome video and series!

[@SergioBobillierC]

Amazing video (as always).

[@sparklemidget]

They should edit this video and insert meltdown and spectre.