[HN Gopher] The Jeff Dean Facts
___________________________________________________________________
The Jeff Dean Facts
Author : ravenical
Score : 355 points
Date : 2026-01-08 13:02 UTC (9 hours ago)
(HTM) web link (github.com)
(TXT) w3m dump (github.com)
| thevillagechief wrote:
| > When Jeff gives a seminar at Stanford, it's so crowded Don
| Knuth has to sit on the floor. (TRUE)
|
| That's actually funny and cool if true. I think what's even more
| impressive is that this stuff was all pre-AI boom.
| scottlamb wrote:
| It probably is. I think the same thing happened when Randall
| Munroe (of xkcd fame) gave a talk at Google. I was there, it
| was crowded, and Don Knuth showed up. 90% sure he sat on the
| floor.
| flir wrote:
| I would definitely give up my seat to Don Knuth.
| scottlamb wrote:
| In theory I would too, but I was also on the floor, and
| believe it or not I didn't notice Don Knuth was there until
| after the talk had started.
| nooks wrote:
| Friends and I nabbed front-row seats to the Munroe talk;
| after a time we were asked to take seats a few rows back to
| make room for Knuth and others. He definitely did not sit on
| the floor.
| scottlamb wrote:
| Well, that shows what my 90% sure memory is worth. I sit
| corrected.
| svat wrote:
| FWIW the XKCD talk at Google is here (wow, 18 years ago! I
| remember watching this video when it was posted):
| https://www.youtube.com/watch?v=zJOS0sV2a24 (Knuth comes up
| to ask a question at 21:30) (Can't tell from the video where
| he was sitting otherwise, though there are definitely at
| least some people sitting on the floor.)
| dekhn wrote:
| Yes, Jeff told me this one personally. Knuth came in right
| before the talk started and the room was full. I think somebody
| later gave up a seat for him.
| stogot wrote:
| I didn't think I'd laugh, but a few of these cheered me up.
| Laughter is such a good medicine.
| callumprentice wrote:
| Agreed! I felt the same way but sitting here with my morning
| coffee chuckling away. A good start to the day.
| VikingCoder wrote:
| In an alternate universe, pi is rational, and Jeff Dean is not.
| saagarjha wrote:
| What's Mustang? Web search?
| bananapub wrote:
| yes
| mike_hearn wrote:
| It is or was the serving component of the main index. The part
| that does the posting list intersections and lookups.
| ChrisMarshallNY wrote:
| Love it!
|
| _> Jeff Dean compiles and runs his code before submitting, but
| only to check for compiler and CPU bugs._
|
| Sadly, I have encountered this, in many "Non-Jeff-Dean"
| developers.
| Xenoamorphous wrote:
| What I've found is some really average developers thinking
| they're Jeff Dean, or at least have that attitude.
| esafak wrote:
| It's nice that a company has senior engineers that are known by
| name and looked up to. It shows that engineers are valued, and a
| meritocracy exists.
| dekhn wrote:
| Yes, but the downside is even highly accomplished engineers
| feel unworthy. For example, when I started in 2008, they said
| everybody should make a "Google Resume" (ongoing list of all
| the stuff you did at Google) and linked to Jeff's as an
| example.
|
| He rewrote the entire indexing pipeline at a critical time
| enabling Google's rapid growth... created mapreduce... helped
| create bigtable & gfs... wrote the search engine that ran for
| over a decade... numerous improvements to search and ads
| quality (back in the days when search and ads quality meant
| something)... and that was just the first few years.
| shemnon42 wrote:
| Everyone at Google has imposter syndrome. If you don't, this
| is how they make sure you get it.
| advisedwang wrote:
| > It shows that engineers are valued
|
| yep
|
| > and a meritocracy exists
|
| not necessarily. It shows the system got one excellent engineer
| to an appropriate position. But it doesn't show that the system
| isn't promoting bozos too, and keeping other excellent
| engineers down.
| jll29 wrote:
| > But it doesn't show that the system isn't promoting bozos
| too, and keeping other excellent engineers down.
|
| Has anyone worked at GOOG and also other corporations? How do
| the alternative cultures compare?
| andy99 wrote:
| My highlight are During his own Google interview,
| Jeff Dean was asked the implications if P=NP were true. He said
| "P = 0 or N = 1." Then, before the interviewer had even finished
| laughing, Jeff examined Google's public certificate and wrote the
| private key on the whiteboard. Jeff Dean wrote an
| O(n^2) algorithm once. It was for the Traveling Salesman Problem
|
| I read it more as a parody of The Most Interesting Man in the
| World as opposed to Chuck Norris.
| jakevoytko wrote:
| "Chuck Norris facts" was a text-only meme format from the mid
| '00s. Stuff like "Chuck Norris is the only man to ever defeat a
| brick wall in a game of tennis" or "When Chuck Norris does
| push-ups, he doesn't push himself up, he pushes the Earth
| down." The Jeff Dean Facts use the same format. It doesn't have
| anything to do with Chuck Norris himself.
| mock-possum wrote:
| I vaguely remember another instance of this around a guy in
| the army - I forgot if it was at boot camp or what the rank
| was, but it was something along the lines of "things I'm no
| longer allowed to do" and just had a bunch of silly military
| joke/prank type things... man I wonder if I could dig that up
| again, I think it might have been late 90s internet.
| OrsonSmelles wrote:
| That would be Skippy's List[0], which as far as I know is
| the seminal work in the genre (at least on the internet). I
| originally learned about it through a (rather less compact)
| version about someone's D&D crimes[1], which was closer to
| my cultural wheelhouse, but the original holds up even if
| you have to google some phrases.
|
| [0] https://skippyslist.com/list/
|
| [1] https://theglen.livejournal.com/16735.html
| 0xWTF wrote:
| > May not pretend to be a fascist stormtrooper, while on
| duty.
| mcmcmc wrote:
| The Dos Equis ad campaign came well after Chuck Norris jokes
| bananapub wrote:
| Someone should IARC the internal one.
| dust-jacket wrote:
| OK "Jeff Dean once shifted a bit so hard it ended up on another
| computer" got a proper chuckle from me
| chihuahua wrote:
| This is the basis for the software that allows you to use a
| single mouse to control a mouse pointer on several computers.
| scottlamb wrote:
| > When Jeff Dean goes on vacation, production services across
| Google mysteriously stop working within a few days. This is
| actually true. ... It's not clear whether this fact is _really_
| true, or whether this line is simply part of the joke, so I 've
| omitted the usual (TRUE) identifier here. Interpret this as you
| see fit :)
|
| I think this one's true-ish. Back in the day when Google didn't
| have good cron services for the corp and production domains [1],
| Jeff Dean's workstation ran a job that made something called
| (iirc) the "protocol buffer debug database". Basically, a big
| file (probably an sstable) with compiled .proto introspection
| data for a huge number of checked-in protobufs. You could use it
| to produce human-readable debug output from what was otherwise a
| fairly indecipherable blob. I don't think it was ever intended
| for production use, but some things that shouldn't have ended up
| using it. I think after Jeff had been on vacation for a while,
| his `prodaccess` credentials expired, the job stopped working,
| maybe the output became unavailable, and some things broke.
|
| Here's a related story I know is true: when I was running Google
| Reader, I got paged frequently for Bigtable replication delay,
| and I eventually traced it to trouble accessing files that shared
| GFS chunkservers with this database. I mentioned it on some
| mailing list, and almost immediately afterward Jeff Dean CCed me
| on a code review changing the file's replication from r=3 to
| r=12. The problem went away.
|
| [1] this lasted longer than you would expect
| jeffbee wrote:
| The other thing that ran under Jeff's desk for a long time was
| Code Search, the old one.
| shadowgovt wrote:
| I remember this. He went on vacation and since he wasn't
| available to login, code search indexing went down for a bit.
| kentonv wrote:
| I submitted this "fact" and it is indeed a true story, exactly
| as you said.
|
| The "global protobuf db" had comments all over it saying it's
| not intended for production-critical tasks, and it had a lot of
| caveats and gotchas even aside from being built by Jeff's
| desktop, but it was so convenient that people naturally ended
| up using it anyway.
| the-rc wrote:
| There was a variant of this that occurred later. By that time
| there might not have been a dependency on Jeff's workstation
| anymore, but the DB, or at least one of its replicas, was
| getting copied to... /gfs/cg/home/sanjay/ -- I don't believe
| it was Jeff this time. At some point, there was a very long
| PCR in the Oregon datacenter, perhaps even the same one that
| happened a few weeks after the 2011 Fukushima disaster. With
| the CG cluster powered off for multiple days, a bunch of
| stuff broke, but in this case the issue might have been
| solved by dumping the data and/or reading it from elsewhere.
| chubot wrote:
| Ha, I also recall this fact about the protobuf DB after all
| these years
|
| Another Jeff Dean fact should be "Russ Cox was Jeff Dean's
| intern"
|
| This was either 2006 or 2007, whenever Russ started. I remember
| when Jeff and Sanjay wrote "gsearch", a distributed grep over
| google3 that ran on 40-80 machines [1].
|
| There was a series of talks called "Nooglers and the PDB" I
| think, and I remember Jeff explained gsearch to maybe 20-40 of
| us in a small conference room in building 43.
|
| It was a tiny and elegant piece of code -- something like ~2000
| total lines of C++, with "indexer" (I think it just catted all
| the files, which were later mapped into memory), replicated
| server, client, and Borg config.
|
| The auth for the indexer lived in Jeff's home dir, perhaps
| similar to the protobuf DB.
|
| That was some of the first "real Google C++ distributed system"
| code I read, and it was eye opening.
|
| ---
|
| After that talk, I submitted a small CL to that directory
| (which I think Sanjay balked at slightly, but Jeff accepted).
| And then I put a Perforce watch on it to see what other changes
| were being submitted.
|
| I think the code was dormant for awhile, but later I saw
| someone named Russ Cox started submitting a ton of changes to
| it. That became the public Google Code Search product [2]. My
| memory is that Russ wrote something like 30K lines of google3
| C++ in a single summer, and then went on to write RE2 (which I
| later used in Bigtable, etc.)
|
| Much of that work is described here:
| https://swtch.com/~rsc/regexp/
|
| I remember someone telling him on a mailing list something like
| "you can't just write your own regex engine; there are too many
| corner cases in PCRE"
|
| And many people know that Russ Cox went on to be one of the
| main contributors to the Go language. After the Code Search
| internship, he worked on Go, which was open sourced in 2009.
|
| ---
|
| [1] Actually I wonder if today if this could perform well
| enough a single machine with 64 or 128 cores. Back then I think
| the prod machines were something like 2, 4, or 8 cores.
|
| [2] This was the trigram regex search over open source code on
| the web. Later, there was also the structured search with
| compiler front ends, led by Steve Yegge.
| chubot wrote:
| Side note: I used this query to test LLM recall: _Do jeff
| dean and russ cox know each other?_
|
| Interesting results:
|
| 1. Gemini pointed me back at MY OWN comment, above, an hour
| after I wrote it. So Google is crawling the web FAST. It also
| pointed to: https://learning.acm.org/bytecast/ep78-russ-cox
|
| This matches my recent experience -- Gemini is enhanced for
| many use cases by superior recall
|
| 2. Claude also knows this, pointing to pages like:
| https://usesthis.com/interviews/jeff.dean/ -
| https://goodlisten.co/clip/the-unlikely-friendship-that-
| shap... (never seen this)
|
| 3. ChatGPT did the worst. It said
|
| _... they have likely crossed paths professionally given
| their roles at Google and other tech circles._ ...
|
| _While I can 't confirm if they know each other personally
| or have worked directly together on projects, they both would
| have had substantial overlap in their careers at Google._
|
| (edit: I should add I pay for Claude but not Gemini or
| ChatGPT; this was not a very scientific test)
| romanhn wrote:
| Not just Google. I had ChatGPT regurgitate my HN comment
| (without linking to it) about 15 minutes after posting it.
| That was a year ago.
| https://news.ycombinator.com/item?id=42649774
| btilly wrote:
| In 2010, due to the China hacking thing, Google locked down its
| network a lot.
|
| At least one production service went down because it relied on
| a job running on Jeff Dean's personal computer that no longer
| had access. Unfortunately I forget what job it was.
| squigz wrote:
| "When God said: "Let there be light!", Jeff Dean was there to do
| the code review."
| m1ck wrote:
| My 3 When Graham Bell invented the telephone, he saw a missed
| call from Jeff Dean. Jeff Dean's PIN is the last 4 digits of pi.
| As a young boy, Jeff Dean reprogrammed his Etch A Sketch to play
| Tetris.
| m00dy wrote:
| can he beat llms ? don't think so.
| dekhn wrote:
| Jeff is so good at AI, he invented much of the infrastructure
| to implement LLMs, mostly to increase the productivity of other
| programmers.
| bigstrat2003 wrote:
| Anyone of modest competence can beat LLMs.
| kentonv wrote:
| Hey! I created Jeff Dean Facts! Not the jokes themselves, but the
| site that collected them.
|
| It was in 2008 I think (give or take a year, can't remember). I
| worked at Google at the time. Chunk Norris Facts was a popular
| Internet meme (which I think later faded when he came out as
| MAGA, but I digress...). A colleague (who wishes to remain
| anonymous) thought the idea of Jeff Dean Facts would be funny,
| and April 1st was coming up.
|
| At the time, there was a team working on an experimental web app
| hosting platform code named Prometheus -- it was later released
| as App Engine. Using an early, internal build I put together a
| web site where people could submit "facts" about Jeff Dean, rate
| each other's facts on a five-star scale, and see the top-rated
| facts. Everything was anonymous. I had a few coworkers who are
| funnier than me populate some initial facts.
|
| I found a few bugs in Prometheus in the process, which the team
| rapidly fixed to meet my "launch date" of April 1st. :)
|
| On the day, which I think was a Sunday, early in the morning, I
| sent an email to the company-wide "misc" mailing list (or maybe
| it was eng-misc?) from a fake email address (a google group alias
| with private membership), and got the mailing list moderator to
| approve it.
|
| It only took Jeff an hour or two to hack his way through the
| back-end servers (using various internal-facing status pages,
| Borg logs, etc.) to figure out my identity.
|
| But everyone enjoyed it!
|
| My only regret is that I targeted the site specifically at Jeff
| and not Sanjay Ghemawat. Back then, Jeff & Sanjay did everything
| together, and were responsible for inventing a huge number of
| core technologies at Google (I have no idea to what extent they
| still work together today). The site was a joke, but I think it
| had the side effect of elevating Jeff above Sanjay, which is not
| what I intended. Really the only reason I targeted Jeff is
| because he's a bit easier to make fun of personality-wise, and
| because "Jeff Dean Facts" sort of rolls off the tongue easier
| that "Sanjay Ghemawat Facts" -- but in retrospect this feels a
| little racist. :(
|
| My personal favorite joke is: Jeff Dean puts his pants on one leg
| at a time, but if he had more than two legs, you'd see his
| approach is actually O(log n).
| bummy_commenter wrote:
| What makes it feel a little racist?
| Lerc wrote:
| >"Jeff Dean Facts" sort of rolls off the tongue easier that
| "Sanjay Ghemawat Facts"
|
| The reason it rolls off the tongue easier is because of the
| familiarity with names of that form. It is making a choice to
| favour a personal cultural similarity. It clearly wasn't done
| with malice, but being reflective about it and noticing that
| it happened is a good thing.
|
| When people talk about privilege, this is a large part of
| what people mean. There's no intended bias, it is just an
| honest choice, but all of our choices are based upon our
| opinions that will inherently have biases of some sort. One
| factor of privilege is when those choices disproportionately
| fall your way because decisions end up being made by people
| who you share a cultural upbringing with. Their intuitive
| decisions value what you value.
|
| Sometimes the only way you can deal with that is by
| acknowledging your intuitions contain that implicit bias and
| dispassionately try and balance them as best you can.
| oncallthrow wrote:
| It's to do with the length of the name. My own name is
| polysyllabic and also wouldn't work as a "Fact", and I'm as
| white as they come.
| Lerc wrote:
| That's kind of the point. In a culture where names
| commonly have a lot of syllables, the length of the name
| is much less of an issue. That tiny discomfort of the
| extra effort to process more syllables disappears when
| it's not considered 'extra'
| oncallthrow wrote:
| I'm not sure I agree. I expect that an Indian would
| similarly be more likely to coin the term "Krish Singh
| Facts" than they would "Sanjay Ghemawat Facts", in
| exactly the same way we do.
|
| I'd be interested to hear from someone from a different
| culture to verify whether this is true or not.
| Lerc wrote:
| I don't know how such things are considered in India
| either (and would also be interested to hear from
| someone). The salient point is that you _do_ value fewer
| syllables in a comedy context. All it takes for someone
| to feel that it might be racist is to recognise that
| fewer syllables in comedy names may not be universal
| across cultures, and that taking an action that elevated
| one person and not another may have inadvertently
| selected someone of one race because of that preference.
|
| It's not an absolute claim being made here. It's just a
| consideration that what we intuitively feel may not be an
| expression of a universally held value.
| peddling-brink wrote:
| I'm no expert, but I certainly wouldn't call that racism. Bias,
| absolutely. And it's important that we acknowledge our biases.
|
| But in a more literal sense, the chance of your joke landing
| was likely higher due to the things that you stated and due to
| your audience and their biases.
|
| I don't see your joke as being in any way harmful towards
| Sanjay aside from potential knock on effects of Jeff Dean being
| more popular. But if you try to calculate every second and
| third order consequence of everything that you do, let alone
| any moments of humor you might have.. Well, you might as well
| lock yourself in a cell now.
| tczMUFlmoNk wrote:
| > I don't see your joke as being in any way harmful towards
| Sanjay aside from potential knock on effects of Jeff Dean
| being more popular
|
| I mean... yeah. When two people are peers and comparably well
| regarded, and one is elevated above the other and enjoys
| increased popularity, familiarity, and respect, and the
| elevation is because that person's name comes from a culture
| that is more aligned with the dominant culture and easier for
| them to engage with... that is a pretty textbook example of
| systemic racism.
|
| I'm not at all saying this to demonize Kenton. We can make
| mistakes and reflect on them later, and that's laudable. But
| it _is_ important to recognize these systems for what they
| are, so that we can notice them when they happen all around
| us every day.
| bummy_commenter wrote:
| I see. I hadn't thought of it from a perspective of
| dominant culture. Looking at it that way, it can appear
| racist.
|
| I looked at it from the perspective of syllable count. Jeff
| Dean is easier to say by that measure. If Jeff were instead
| named Alexander Chesterton, would he still be the obvious
| choice to head the facts? My takeaway from this is that a
| single-syllable name is perhaps a great boon.
| elijaht wrote:
| Sanjay is/was well known enough that you could have just
| used "Sanjay facts"
| derangedHorse wrote:
| I find the assumption that Jeff Dean sounded better with
| these jokes because it sounds American to be a bigger issue
| than immediately acknowledging that it's probably because
| it's less syllables. These type of jokes are rapid fire and
| a lengthy name just fits better whether it's 'Jeff Dean' or
| 'Neel Patel'.
| refulgentis wrote:
| Seeing this reminds me Sanjay is two syllables
| kentonv wrote:
| Thanks, you explained this better than I could.
|
| I'm not calling myself Hitler here, I think it was a mild
| offense. But in retrospect the site could have been about
| both of them, with competing facts, and that could have
| been really cool. Oh well.
| jrowen wrote:
| I don't think it's really fair to call it racism. That is
| such a loaded accusation to levy today that it should only
| be used if someone really wronged another person.
|
| We all have cultural biases and familiarities, is that
| wrong? By this definition, we're all racist. Maybe that's
| true but it kind of ceases to be a useful distinction at
| that point. I wholeheartedly agree with your last sentence,
| but I don't know if throwing around the r-word is helpful.
| rayiner wrote:
| > that is a pretty textbook example of systemic racism.
|
| It's not "racism." There's plenty of Indians with names
| that are easy for English speakers. Conversely, the same
| situations would've presented itself if the other person
| was any sort of white Eastern European.
|
| In fact, calling this "racist" is itself racist. I have
| close friends with family names from Poland or Croatia
| where we don't even try to pronounce their names correctly.
| Nobody feels bad about that. But for some reason if it's a
| "brown person" we're suddenly super sensitive about it.
| _That_ is differential treatment based on race.
|
| People get awkward about how to pronounce my name because
| I'm brown. But it's hard to pronounce because it's
| misspelled Germanic! They wouldn't act that way if I was a
| white guy with the same name.
| kentonv wrote:
| Are we... arguing about what happened in my head?
|
| As the world's foremost expert about what happened in my
| head, do I get to, like, pick a winner here?
|
| If so I pick tczMUFlmoNk, I think their description is
| accurate. (I think you might want to re-read it as it
| feels like you are responding to something else.)
|
| If I don't get to pick, this is quite weird! "People on
| Hacker News tell me I'm wrong about my own thoughts." was
| not on my -- actually wait, that doesn't sound unexpected
| at all now that I write it out! OK, carry on.
| rayiner wrote:
| You wrote what your thoughts were. I'm just weighing in
| on whether your thoughts are "racist." To the extent you
| feel sensitive about the issue because someone has darker
| skin, where you probably wouldn't have written that part
| of the post if the other guy were Polish, that's racist.
| It's racist to treat people differently based on skin
| color, even if you're well intentioned about it.
| refulgentis wrote:
| You're conflating two different things:
|
| 1. The original choice: Kenton picked "Jeff Dean" because
| the name was more familiar/rhythmic in English. This
| wasn't about skin color, it was about name patterns.
| You're right that a Polish surname could have the same
| issue, and in that, you're demonstrating complete
| understanding of the issue at hand.
|
| 2. The reflection afterward: Recognizing that name-
| familiarity advantages _systematically_ correlate with
| certain cultural backgrounds more than others isn 't
| "differential treatment based on skin color", it is
| observing a statistical pattern in outcomes.
|
| And here's the key point: given Kenton's explanation,
| they are indicating they _would_ reflect the same way if
| Sanjay had been Polish with an unfamiliar surname. You
| 're arguing with Kenton about what Kenton thinks and
| could think... while Kenton is right here. At some point
| you have to engage with what he's actually saying rather
| than insisting you understand his mind better than he
| does.
| kentonv wrote:
| Yes, I actually do think if Sanjay Ghemawat were instead
| Wojciech Przemyslaw Kosciuszko-Wisniewski, white European
| but otherwise an equal engineer, and I chose to elevate
| Jeff Dean over him, I would later feel equally bad about
| it.
|
| (Which again to be clear I'm am not riven with guilt
| here, I just think maybe given another chance I would
| have made it about both of them.)
| bigstrat2003 wrote:
| It's not remotely racist. OP is being self critical for no
| good reason.
| morley wrote:
| Ah, I knew I recognized the friendship between Jeff and Sanjay
| -- they were the subject of a New Yorker article in 2018:
|
| https://www.newyorker.com/magazine/2018/12/10/the-friendship...
|
| EDIT: And HN at the time:
|
| https://news.ycombinator.com/item?id=18588697
| liquidgecka wrote:
| That meme started in early 2007 I believe. I started in 2006
| and was in ZRH by 2008 and it was around long before I made
| that move.
| omoikane wrote:
| > My only regret is that I targeted the site specifically at
| Jeff and not Sanjay Ghemawat.
|
| Later version of the site was generalized so that people can
| submit facts for any user. I think Jeff Dean still has all the
| funniest fact though.
| oncallthrow wrote:
| > but in retrospect this feels a little racist. :(
|
| It's not racist. It's just to do with name length.
| ariwilson wrote:
| Hi Kenton! I was the recent grad you handed this web app off to
| after you built it, so I expanded Jeff Dean Facts so that
| anyone could create and rate facts about anyone at Google :).
| There were a ton of team in-jokes added before I stopped
| working on it - O(5k) IIRC! :)
|
| This web app was also how I learned the pain of maintaining a
| live web service with a lot of ever-changing dependencies. How
| I sighed when the AppEngine version changed and I had to fix
| things again...
|
| I handed it off again before I left Google but I have no memory
| of who that was to unfortunately :(.
| kridsdale3 wrote:
| I just searched Moma, and your note about it going down is
| the most recent update on this front. Interestingly though,
| it looks like Moma itself has a custom SERP renderer for Jeff
| Dean facts that came up when I searched. The example fact
| that came up was hilarious, but I guess I shouldn't share it
| on public HN.
| kentonv wrote:
| Hi Ari,
|
| Thanks so much for falling for my trick and taking it over, I
| was getting pretty sick of dealing with the same issues you
| describe. :)
|
| One of the reasons Cloudflare Workers has a policy that we
| absolutely never break deployed code, ever. (Well... at least
| not intentionally...)
| swyx wrote:
| > Jeff & Sanjay did everything together,
|
| my nonexpert impression is jeff keeps much more of a public
| profile. hence the natural celebrity goes to him. was this not
| true way back in the day?
| kentonv wrote:
| I feel like Jeff's public profile has grown quite a bit since
| then. Note that in 2008 he wasn't doing anything related to
| AI yet -- none of that had even started. That has since given
| him somewhat of a more public role, whereas Sanjay has stayed
| on infrastructure which is more internal-facing. I do think
| Jeff Dean Facts in itself has played some part in enhancing
| his celebrity status, too.
|
| With that said, I suppose it's hard for me to say what the
| public perception of the two was in 2008 as I only knew of
| either of them from working there.
| vessenes wrote:
| Re Jeff and Sanjay - they recently were on Dwarkesh together I
| believe - so it looks like the partnership is still going
| strong. Regarding Dean over Ghemawat facts, the vibe from the
| convo is that Sanjay is the (very slightly) junior partner of
| the two, or at least he lets Jeff do more of the talking. Very,
| very nice vibes hearing them talk, and their war stories are
| clearly nuts.
| chrfrasco wrote:
| It was Jeff Dean and Noam Shazeer:
| https://www.dwarkesh.com/p/jeff-dean-and-noam-shazeer
| dekhn wrote:
| The one thing I noticed when I worked near Jeff and Sanjay
| and talked to them over coffee is that Jeff is the smart one,
| but Sanjay is the wise one.
|
| Jeff always had an idea how to make something a bit faster
| using a clever trick, but Sanjay would respond by coming up
| with how to express the abstraction in a way that other
| mortals could comprehend, or just telling Jeff it wasn't a
| good idea because it would make things more difficult to
| maintain.
|
| Jeff was also prone to dad jokes, Sanjay's humor was far more
| subtle. Both were awesome to talk to and one of my proudest
| moments was when Jeff read a document proposal I wrote
| ("Google should get involved in Genomics Research and Drug
| Discovery") and took it seriously.
| keybored wrote:
| Guy happens to be the lead of Google AI right now.
| lysace wrote:
| My outsider understanding: Google AI (a Google team which Jeff
| Dean ran) was merged with DeepMind to create Google DeepMind (a
| subsidiary of Alphabet, like Google).
|
| Demis Hassabis is the CEO of Google DeepMind and Jeff Dean is
| now the Chief Scientist of Google.
|
| https://en.wikipedia.org/wiki/Google_DeepMind
|
| https://research.google/people/jeff/
|
| _I joined Google in mid-1999, and I 'm currently Google's
| Chief Scientist, focusing on AI advances for Google DeepMind
| and Google Research. My areas of focus include machine learning
| and AI and applications of AI to problems that help billions of
| people in societally beneficial ways. I have a broad variety of
| interests, including machine learning, large-scale distributed
| systems, computer systems performance, compression techniques,
| information retrieval, application of machine learning to
| search and other related problems, microprocessor architecture,
| compiler optimizations, and the development of new products
| that organize information in new and interesting ways._
| nickstaggs wrote:
| Maybe I just run in different circles but I was always under the
| impression that the so called Chuck Norris of programming was Jon
| Skeet, another rather "famous" google employee
| billbrown wrote:
| He's the Chuck Norris of StackOverflow, maybe.
| dysoco wrote:
| Yeah I thought exactly the same, but I guess Jon Skeet is from
| a different era altogether, we're moving into a world where
| many programmers perhaps have never even entered StackOverflow.
| I feel old.
| Sesse__ wrote:
| Jon Skeet was very much a local hero on StackOverflow, and on
| StackOverflow only.
| freeCandy wrote:
| To me, the Chuck Norris of programming has to be Fabrice
| Bellard
| linsomniac wrote:
| Reminds me of https://en.wikipedia.org/wiki/The_Story_of_Mel
| shagie wrote:
| As I write this, catb is not serving promptly... so
| https://users.cs.utah.edu/~elb/folklore/mel.html
|
| I also recommend Monktoberfest 2016: Bryan Cantrill - Oral
| Tradition in Software Engineering :
| https://youtu.be/4PaWFYm0kEw?si=nqfxSae52-89x5Ye&t=653
| lookingdesk wrote:
| Jeff Dean liquidated Google's entire AI ethics team because they
| wouldn't revise an academic publication to align with the
| corporate PR spin on AI.
| whynotminot wrote:
| As far as I can tell, no one seems to think much of value was
| lost.
| shadowgovt wrote:
| It turns out when you usher the dissenters out of the room,
| you hear a lot less dissent.
| whynotminot wrote:
| It's not like they were summarily executed. They are much
| freer now outside of corporate control to speak their minds
| as they please.
|
| The only real question is if anyone deems them worth
| listening to.
| shadowgovt wrote:
| I mean, I follow them.
|
| Their problem domain is pretty niche and they're pretty
| technical on it so I don't doubt their traction is mostly
| academics.
| keeganpoppen wrote:
| even at the time that was the verdict
| foolfoolz wrote:
| ai ethics was/is useless. it felt a lot like the movie
| industry of the 1930s saying they will police themselves just
| to keep any bigger regulator away
| dsr_ wrote:
| ... And then they didn't!
| jll29 wrote:
| To say "AI ethics is useless" is itself useless.
|
| Morality is not there to be useful, right or wrong in moral
| sense are normative categories not utilitarian ones.
|
| But what you possibly may mean is really AI ethics self-
| regulation by large tech corporation does not work. (If
| that was your intended statement, I'd agree.)
| morcus wrote:
| I'm having trouble following what exactly this means.
|
| So Jeff wanted the team to modify an existing publication to
| fit the PR spin on AI, the ethics team refused, and Jeff
| dissolved the team?
| lookingdesk wrote:
| https://www.technologyreview.com/2020/12/04/1013294/google-a.
| ..
| chubot wrote:
| This is overstating it by a lot. Jeff was the AI lead at the
| time, and there was a big conflict between management and the
| ethics team
|
| And I actually think Google needs to pay more attention to AI
| ethics ... but it's a publically traded company and the
| incentives are all wrong -- i.e. it's going to do whatever it
| needs to do keep up with the competition, similar to what
| happened with Google+ (perceived competition from Facebook)
| tziki wrote:
| You mean he fired one person who threatened to quit if the
| changes to the paper weren't to their liking? Or am I
| misremembering?
| shemnon42 wrote:
| Just another Jeff Dean optimizing out unneeded code story.
| lemoncucumber wrote:
| That incident was the first time I ever heard of Jeff Dean and
| remains the main thing I associate him with.
| scottyah wrote:
| Isn't it crazy how the media can do that? It really doesn't
| matter how much good you do in the world if your enemies
| speak louder. At least in the public's perception.
| jll29 wrote:
| Not sure if he was told to stop the paper and fire the team,
| or whether he decided that himself.
|
| But in any case, it's a stain on an overwise exceptionally
| brilliant career with wonderful software engineering
| achievements.
|
| I wonder if they ever wondered if they'd do it again?
| benzguo wrote:
| loved this so much i made a jeff dean persona for my AI:
| https://www.zo.computer/pub/persona/prs_WtLmiGHQmHqaMKIy
| justinchen7 wrote:
| Funny, but also a reminder of how rare it is to find people who
| combine deep technical ability with the calm, high-leverage
| decision-making that scales teams. Memes aside, those are the
| folks who quietly shape entire fields.
| dhruv3006 wrote:
| https://static.googleusercontent.com/media/research.google.c...
|
| To me this will remain his best work.
| leopoldj wrote:
| A few more:
|
| Jeff Dean doesn't use a compiler; he just glares at his source
| code until it executes.
|
| Jeff Dean once optimized a sleep(10) call to return in 5 seconds.
|
| Jeff Dean's keyboard doesn't have a Backspace key; he simply
| doesn't make mistakes.
|
| /end. There's no need to get up. I will see myself out.
| philipwhiuk wrote:
| See also https://meta.stackexchange.com/questions/9134/jon-skeet-
| fact...
| bhickey wrote:
| I once mailed a CL to Sanjay. He replied, "This is outside of my
| expertise. Can you send it to Jeff?"
| seanmcdirmid wrote:
| One of my more junior teammates got their CL assigned to Sanjay
| for review, she had no idea who he was and I just told her to
| look at all her new badges tomorrow.
| acoster wrote:
| IME Sanjay responds to CLs way faster than I expected.
| seanmcdirmid wrote:
| I've never had in for a review at google, I think it only
| happens if you change something very top level. I did an
| internship under him the summer before he joined Google at
| Dec/Compaq SRC though. I learned a lot of tricks from him
| then (like using graphviz to print out compiler graphs to
| do debugging).
| postscapes1 wrote:
| I am only semi technical so most of these go right over my head,
| but after watching a ton of Jeff Dean interviews, etc it is
| really fun to see how a 10-100x engineer can operate over such a
| long career (while seemingly a normal and kind person to boot)
| devin wrote:
| The more specific the "fact" is to the target, the better IMO.
|
| - Bruce Schneier facts - https://www.schneierfacts.com/
|
| - Doug McIlroy facts -
| https://github.com/mischief/9problems/blob/master/lib/dougfa...
| shadowgovt wrote:
| I remember one that isn't in the list. Paraphrasing:
|
| "Jeff Dean has access to the priority above P1. He's only used it
| once. It's why February only has 28 days."
| yongjik wrote:
| I also remember that but I think it was attributed to someone
| else. The site hosted several (internally famous person) facts,
| but none of them were as famous as Jeff Dean.
| pss314 wrote:
| New Yorker published an interesting article on Jeff Dean and
| Sanjay Ghemawat few years ago - The Friendship That Made Google
| Huge [0]
|
| [0]: https://www.newyorker.com/magazine/2018/12/10/the-
| friendship...
| rednafi wrote:
| Another one I have heard is "Jeff Dean's stare can fix bitrot"
| jackblemming wrote:
| Jeff Dean is a lot smarter than me, more accomplished, and more
| talented. But let's be honest. He was a big part of TensorFlow
| and TensorFlow sucks. And I imagine it reflects a lot about Jeff
| Dean internally. Smart, clever, but maybe over complicated or
| over engineered. And that itself reflects hugely at what Google
| tends to like, and why he's so successful (at Google).
|
| And if we're being brutally honest, I wonder how he would have
| faired at somewhere like Bell Labs ;)
| hvenev wrote:
| > Jeff once simultaneously reduced all binary sizes by 3% and
| raised the severity of a previously known low-priority Python bug
| to critical-priority in a single change that contained no Python
| code.
|
| This sounds really plausible. A change to the C toolchain/library
| (for example, specialized/inlined memcpy) may affect binary sizes
| significantly, and may change the behavior of something the C
| standard leaves undefined (for example, memcpy with overlapping
| arguments).
| ripe wrote:
| What does "readability" mean? It's mentioned in several of these
| jokes: "binary readability", etc.
| bubblicious wrote:
| readability grants a code reviewer the power to approve changes
| in a specific language
| shemnon42 wrote:
| I was wondering if someone was going to ask. It's the most
| bizzare aspect of code reviews at Google.
|
| And "Readability" doesn't mean you are good at a language, it
| means you are good at it in the way Google uses it. C++
| readability is the poster child of this. Borgcron, not so
| much.
| sowbug wrote:
| A bit more detail: long ago, before the time of the Great
| Brace War, people wrote code using all sorts of styles:
| tabs/spaces, short or long variable/function names, Hungarian
| notation or not, comments or not, long blocks or short, and
| so on. You could often tell which of your teammates wrote a
| block of code simply by newline usage. This made it hard to
| read and contribute code in a less familiar part of the
| codebase.
|
| Google mitigated this problem at scale by introducing the
| concept of "readability" for each language (C++, Java, and
| Python, simpler times). If you had readability, you could
| approve another person's change for that language. If you
| didn't, you could still review the code, but the reviewee
| also had to go find someone else with readability.
|
| After you'd accumulated a certain number of commits in a
| language, you could try to get your own readability by
| bundling up your CLs (changelists) and submitting them to the
| readability queue, where a certain group of senior people
| with readability would evaluate whether your code was
| sufficiently idiomatic. This process could take months, or
| even years if you didn't write much in a particular language.
| In any event, it felt like a real achievement to get
| readability.
|
| The upshot of all this was that most code at Google felt
| authorless in a good way: if you knew and expected Google
| style, all the codebase felt the same, and you could
| concentrate on the logic flow rather than the regional
| dialect. And needless to say all the energy wasted on whose
| style was best was squelched in the readability queue.
|
| This is all past tense because I last wrote code for Google
| more than 10 years ago, and I'm sure the process has changed
| since then. Code formatters, shared editor defaults, and
| presubmit checks have surely automated away a lot of the
| toil, and there's much less of a monorepo culture these days,
| so there are probably more style dialects (in addition to
| many, many more permitted languages).
| zhengyi13 wrote:
| I left in 2023. From memory at that time:
|
| 1) go kinda eliminates a lot of the reasons for style
| guides to exist w/ `go fmt` and separately, I think the Go
| readability team made a conscious decision to approach
| readability differently anyway,
|
| 2) ... once you had a couple people on your local team w/
| readability, if your team wanted to do things a certain
| way, well, style guides and formal readability wasn't
| really an issue anymore.
| desi_ninja wrote:
| We need a Dave Cutler facts equivalent too. But the ppl who could
| have made this are probably retired or
| furyofantares wrote:
| > Unsatisfied with constant time, Jeff Dean created the world's
| first O(1/n) algorithm.
|
| I can think of a lot of 1/n algorithms! Head, Tail...
| nojvek wrote:
| Those are still O(1)
| furyofantares wrote:
| Right, lol
| theodric wrote:
| This is the sort of thing that's perfect as a fortune file, so
| here you go:
| https://github.com/theodric/fortitude/tree/master/jeffdeanfa...
| Bost wrote:
| The TheJeffDeanFacts repo contains no issues. (TRUE)
| Myrmornis wrote:
| Any recommendations for a talk by him to watch or something
| written by him to read?
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