The Jeff Dean Facts

(github.com)

483 points | by ravenical 23 hours ago

44 comments

  • kentonv 21 hours ago
    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).

    • sghemawat 8 hours ago
      Hi Kenton! No worries at all. I tend to be quieter than Jeff anyway (less public speaking etc.) and I am happy to not have a dedicated website. :-). -Sanjay
      • kentonv 8 hours ago
        Hey Sanjay, long time no see. Thanks for the note!

        But I'm fully aware you wouldn't want a "Sanjay Facts", and that's not the point. ;)

      • Ozzie_osman 2 hours ago
        You are both legends. Your original MapReduce paper is what inspired me to work for Google (2006-2009), narrowly dodging a career as a quant on Wall Street.
    • ariwilson 17 hours ago
      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 :(.

      • kentonv 14 hours ago
        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...)

      • kridsdale3 16 hours ago
        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.
    • peddling-brink 20 hours ago
      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.

      • bigstrat2003 19 hours ago
        It's not remotely racist. OP is being self critical for no good reason.
      • tczMUFlmoNk 20 hours ago
        > 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.

        • derangedHorse 19 hours ago
          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 18 hours ago
            Seeing this reminds me Sanjay is two syllables
        • jrowen 18 hours ago
          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.

          • istjohn 11 hours ago
            > By this definition, we're all racist. Maybe that's true but it kind of ceases to be a useful distinction at that point.

            Does it? I would argue that recognizing that we all swim in a soup of cultural biases and familiarities that advantage some people and disadvantage others is a noteworthy insight, an insight with practical implications. After all, we aren't volitionless molecules bouncing off walls. What if we made an effort to observe these biases more closely, to study there effects, and to better understand the way they effect our own behaviour? Then, what if we made an effort to counteract these biases, first in our own behaviour and then in our communities?

        • bummy_commenter 19 hours ago
          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 18 hours ago
            Sanjay is/was well known enough that you could have just used “Sanjay facts”
        • rayiner 16 hours ago
          > 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 15 hours ago
            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 15 hours ago
              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 14 hours ago
                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 14 hours ago
                  Yes, I actually do think if Sanjay Ghemawat were instead Wojciech Przemysław Kościuszko-Wiśniewski, 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.)

                  • rayiner 13 hours ago
                    What you said was “in retrospect this feels a little racist.”

                    Obviously what’s in your head specifically is idiosyncratic to you. But the feeling you’re having certainly happens more generally, and is based on general social understandings. That’s what I’m commenting on.

                    If I say, “this feels a little rude,” isn’t it fair for people to chime in as to whether it’s actually rude by reference to general social standards?

                    • kentonv 10 hours ago
                      If I said I'd done something rude and people then argued with as much fervor about whether I'd actually been rude as they are arguing here, I would actually find it pretty weird.
                    • quadrifoliate 10 hours ago
                      I feel like most of us understand roughly what 'kentonv means. He unconsciously put Sanjay in an out-group and feels bad about it. I for one comment Kenton for owning up to it. It's a hard thing to do.

                      For what it's worth, I personally regard Sanjay in just as much awe as Jeff and understand that the meme is just an Internet meme and nothing more.

                      • kentonv 10 hours ago
                        That's the ironic thing too... honestly, while I couldn't say that one or the other is a better engineer... I would say I personally identified more with Sanjay's approach and style.
                      • rayiner 7 hours ago
                        > I feel like most of us understand roughly what 'kentonv means. He unconsciously put Sanjay in an out-group and feels bad about it.

                        But do you feel bad about it because he's brown and you wouldn't think twice about it if he were white? Frankly, the heightened sensitivity feels worse to me than actual racism.

                        • scott_w 5 hours ago
                          > Yes, I actually do think if Sanjay Ghemawat were instead Wojciech Przemysław Kościuszko-Wiśniewski, white European but otherwise an equal engineer, and I chose to elevate Jeff Dean over him, I would later feel equally bad about it.

                          You need to take a breath, read what people write, and stop trying to win the argument.

        • kentonv 19 hours ago
          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.

    • morley 20 hours ago
      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

    • xnx 1 hour ago
      > I have no idea to what extent they still work together today

      They just got their own (unofficial) Lego set: https://x.com/JeffDean/status/2006581022666928415

    • vessenes 14 hours ago
      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.
      • dekhn 13 hours ago
        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.

        • ramraj07 11 hours ago
          Should google have involved though? Calico, Verily, isomorphic etc seem like theyre destined to not succeed.
          • dekhn 11 hours ago
            At the time I first got involved, Google Health was still a thing but it was clear it was not going to be successful. I felt that Google's ML (even early on, they had tons of ML, just most of it wasn't known externally) was going to be very useful for genomics and drug discovery.

            Verily was its own thing that was unrelated to my push in Research. I think Larry Page knew Andy Conrad and told him he could do what he wanted (which led to Verily focusing on medical devices, which is a terrible industry to be in). They've pivoted a few times without much real success. My hope is that Alphabet sheds Verily (they've been trying) or just admit it's a failure and shut it down. It was just never run with the right philosophy.

            Calico... that came out of Larry and Art Levinson- I guess Larry thought Art knew the secret to living forever and by giving him billions Art would come up with the solution to immortality and Larry would have first access to it. But they were ultra-secretive and tried to have the best of both worlds- full access to Google3 and borg, but without Googlers having any access to calico. That, combined with a number of other things, have led Calico to just be a quiet and not very interesting research group. I expect it to disband at some point.

            Isomorphic is more recent than any of the stuff I was involved in, and is DeepMind (specifically Demis's) attempt to commercialize their work with AlphaFold. However, everybody in the field knows the strategy of 1. solve protein structure prediction 2. ??? 3. design profitable drugs and get them approved... is not a great strategy because protein structure determine has not ever been the rate limiting step to identifying targets and developing leads. I agree I don't really see a future for it but Demis has at least 10-20 years of runway before he has to take off or bail.

            All of my suggestions were just for Google to do research with the community and publish it (especially the model code and weights, but also pipelines to prep data for learning) and turn a few of the ideas into products in Google Cloud(that's how Google Genomics was born... I was talking to Jeff, and he said "if we compress the genome enough, we can store it all on Flash, which would make search fast but cheap, and we'd have a useful product for genomics analysis companies"). IMHO Jeff's team substantially achieved their goals before the DeepMind stuff- DeepVariant was well-respected, but almost every person who worked on it and related systems got burned out and moved on.

            What is success, anyway, in biotech? Is it making a drug that makes a lot of money? What if you do that, but it costs so much that people go bankrupt taking it? Or is the goal to make substantial improvements to the technology, potentially discovering key biological details that truly improve people's lives? Many would say that becoming a successful real estate ownership company is the real destination of any successful pharma/biotech.

            • ramraj07 10 hours ago
              Whoa. Finally someone I relate with! Thanks for such amazing intel!

              In my opinion forays into biology by moonshot hopefuls fail for one of two reasons: either they completely ignore all the current wisdom from academia and industry, or they recruit the very academia people who are culturally responsible for the science rot we have at this time. Calico (and CZI, and im starting to fear, Arc) fell prey to the latter. Once you recruit one tenured professor IMO youre done. The level of tenure track trauma and academic rot they bring in can burn even a trillion dollars into dead-end initiatives.

              IMO (after decades of daydreaming about this scenario), the only plausible way to recreate a Bell labs for Biology is to start something behind a single radical person, and recruit the smartest undergrads into that place directly. Ensure that they never become experts at just one thing so they have no allegiance to a method or field. And then let that hoarde loose on a single problem and see what comes out. For better or worse neuralink seems to be doing that right. Just wish they didnt abuse the monkeys that much!

              To me success in biotechnology is if I measurably help make a drug that makes a person smile and breathe easy that would otherwise not have. Surprisingly easy and hard at the same time.

      • chrfrasco 14 hours ago
      • kentonv 10 hours ago
        Having worked with them I would say Sanjay is certainly NOT the "junior" partner. Nor vice versa. They have different strengths but I couldn't say that one or the other is a better engineer overall.
    • oncallthrow 17 hours ago
      > but in retrospect this feels a little racist. :(

      It’s not racist. It’s just to do with name length.

    • omoikane 17 hours ago
      > 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.

    • swyx 15 hours ago
      > 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 14 hours ago
        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.

    • liquidgecka 19 hours ago
      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.
    • rramadass 7 hours ago
      Your job is unfinished :-)

      You still have to create a Youtube channel for Jeff Dean/Sanjay Ghemawat (slayers of code!) like "Entertaining AI" did for "Chuck Norris" - https://www.youtube.com/@Entertaining_AI

    • westurner 10 hours ago
      Maybe both in the URL?

      You could add a meme generator that's like the Django docs tutorial with the internet web-poll

    • bummy_commenter 20 hours ago
      What makes it feel a little racist?
      • Lerc 17 hours ago
        >"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 17 hours ago
          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 16 hours ago
            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 16 hours ago
              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 16 hours ago
                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.

  • scottlamb 21 hours ago
    > 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

    • chubot 20 hours ago
      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 18 hours ago
        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 16 hours ago
          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
          • lossyalgo 48 minutes ago
            Hopefully YCombinator can afford to pay for the constant caching of all HN comments. /s :)
    • kentonv 21 hours ago
      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 17 hours ago
        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.
    • btilly 19 hours ago
      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.

    • jeffbee 21 hours ago
      The other thing that ran under Jeff's desk for a long time was Code Search, the old one.
      • shadowgovt 20 hours ago
        I remember this. He went on vacation and since he wasn't available to login, code search indexing went down for a bit.
  • andy99 21 hours ago
    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 21 hours ago
      "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 19 hours ago
        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 19 hours ago
          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 18 hours ago
            > May not pretend to be a fascist stormtrooper, while on duty.
    • mcmcmc 18 hours ago
      The Dos Equis ad campaign came well after Chuck Norris jokes
  • pss314 20 hours ago
    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...

  • dust-jacket 21 hours ago
    OK "Jeff Dean once shifted a bit so hard it ended up on another computer" got a proper chuckle from me
    • chihuahua 19 hours ago
      This is the basis for the software that allows you to use a single mouse to control a mouse pointer on several computers.
  • hvenev 18 hours ago
    > 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).

    • astrange 10 hours ago
      I have such a Python bug right now because of something that fork()s in a way that can't posix_spawn(). One of those is a lot easier to make performant than the other.
  • devin 20 hours ago
    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...

    • never_inline 3 hours ago
      > Bruce Schneier intercepts all your internal monologues by a man-in-the-middle attack.
  • ChrisMarshallNY 21 hours ago
    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 15 hours ago
      What I’ve found is some really average developers thinking they’re Jeff Dean, or at least have that attitude.
  • thevillagechief 22 hours ago
    > 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.

    • dekhn 21 hours ago
      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.
    • scottlamb 21 hours ago
      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.
      • nooks 20 hours ago
        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 20 hours ago
          Well, that shows what my 90% sure memory is worth. I sit corrected.
      • svat 20 hours ago
        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.)
      • flir 21 hours ago
        I would definitely give up my seat to Don Knuth.
        • scottlamb 21 hours ago
          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.
  • m1ck 21 hours ago
    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.
  • postscapes1 20 hours ago
    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)
  • dhruv3006 21 hours ago
    • hxtk 7 hours ago
      Even with the ellipsized link I knew you were talking about one of a few things because the link shows up as `:visited` for me... had to be either BigTable, MapReduce, or Spanner. All good reads.
  • wernsey 4 hours ago
    There is also a thread on Stack Exchange [1] for John Skeet facts, who has the most reputation there.

    [1]: https://meta.stackexchange.com/questions/9134/jon-skeet-fact...

  • linsomniac 21 hours ago
  • bhickey 21 hours ago
    I once mailed a CL to Sanjay. He replied, "This is outside of my expertise. Can you send it to Jeff?"
    • seanmcdirmid 20 hours ago
      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 19 hours ago
        IME Sanjay responds to CLs way faster than I expected.
        • seanmcdirmid 19 hours ago
          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).
  • ripe 18 hours ago
    What does "readability" mean? It's mentioned in several of these jokes: "binary readability", etc.
    • bubblicious 18 hours ago
      readability grants a code reviewer the power to approve changes in a specific language
      • sowbug 16 hours ago
        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 14 hours ago
          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.

      • shemnon42 16 hours ago
        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.

        • hn_go_brrrrr 3 hours ago
          Did you mean Borgmon? Borgcron is just GCL.

          Sawzall is another good example of an unreadable language.

    • utopcell 9 hours ago
      It is a formal process via which it is confirmed that you know enough of X to submit code to the codebase, where X can be c++, java, python, etc. If you don't have X readability, then, in addition to your main code reviewer, you need to have a readability reviewer look at your code, who will be focusing only on X, not the logic of your code.
  • leopoldj 21 hours ago
    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.

  • VikingCoder 22 hours ago
    In an alternate universe, pi is rational, and Jeff Dean is not.
  • Bost 14 hours ago
    The TheJeffDeanFacts repo contains no issues. (TRUE)
  • justinchen7 21 hours ago
    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.
  • furyofantares 15 hours ago
    > 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...

  • nickstaggs 21 hours ago
    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
    • freeCandy 18 hours ago
      To me, the Chuck Norris of programming has to be Fabrice Bellard
    • billbrown 21 hours ago
      He's the Chuck Norris of StackOverflow, maybe.
    • dysoco 18 hours ago
      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__ 14 hours ago
        Jon Skeet was very much a local hero on StackOverflow, and on StackOverflow only.
        • tiffanyh 9 hours ago
          Claude & Codex are still learning from Jon Skeet.
  • sidcool 8 hours ago
    Jeff Dean achieved a Weismann score of 42.
  • stogot 22 hours ago
    I didn’t think I’d laugh, but a few of these cheered me up. Laughter is such a good medicine.
    • callumprentice 22 hours ago
      Agreed! I felt the same way but sitting here with my morning coffee chuckling away. A good start to the day.
  • Myrmornis 13 hours ago
    Any recommendations for a talk by him to watch or something written by him to read?
  • desi_ninja 17 hours ago
    We need a Dave Cutler facts equivalent too. But the ppl who could have made this are probably retired or
  • bananapub 21 hours ago
    Someone should IARC the internal one.
  • shadowgovt 20 hours ago
    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 13 hours ago
      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.
  • saagarjha 22 hours ago
    What’s Mustang? Web search?
    • mike_hearn 20 hours ago
      It is or was the serving component of the main index. The part that does the posting list intersections and lookups.
    • utopcell 9 hours ago
      Web Search Serving. Many generations ago.
    • bananapub 21 hours ago
      yes
  • theodric 14 hours ago
    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...
  • squigz 21 hours ago
    "When God said: "Let there be light!", Jeff Dean was there to do the code review."
    • dekhn 10 hours ago
      I think this makes more sense: "When God said: "Let there be light!", Jeff Dean said "LGTM, Approve"
  • keybored 21 hours ago
    Guy happens to be the lead of Google AI right now.
    • lysace 21 hours ago
      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.

  • esafak 21 hours ago
    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 19 hours ago
      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 19 hours ago
        Everyone at Google has imposter syndrome. If you don't, this is how they make sure you get it.
      • zerr 12 hours ago
        Wasn't Peter Norvig one of the key people behind Google Search? Would it be correct to say that scientists did the research, maybe reference implementations in Lisp or Python, and later Jeff Dean did the actual C++ production?
        • dekhn 12 hours ago
          Peter worked on search, yes. I think he mainly focused on quality. See his comment on "Managing Gigabytes" (https://www.amazon.com/review/R33MIMY7A7C2H8/ref=cm_cr_srp_d...) which was an early reference for the compression techniques used to make search fast.

          The way jeff described it was that there was a very early contingent who took Larry's original code and made a production system out of it, but it wasn't very good- the indexer basically had to be run all the way through without errors to make a new index- and that was delaying a release of a fresh new index, so results were getting stale. At that point Jeff "invented" mapreduce (the shuffle stage was Sanjay) and wrote the new indexer and the search engine as well.

          I'm not aware of any LISP implementation of the Google search engine; if there was one, it would have been extremely early, like in the stanford days, I think.

    • advisedwang 19 hours ago
      > 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 14 hours ago
        > 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?

  • rednafi 19 hours ago
    Another one I have heard is "Jeff Dean's stare can fix bitrot"
  • philipwhiuk 21 hours ago
  • macybosts 21 hours ago
    [dead]
  • stefantalpalaru 20 hours ago
    [dead]
  • unit149 3 hours ago
    [dead]
  • m00dy 21 hours ago
    can he beat llms ? don't think so.
    • dekhn 19 hours ago
      Jeff is so good at AI, he invented much of the infrastructure to implement LLMs, mostly to increase the productivity of other programmers.
    • bigstrat2003 19 hours ago
      Anyone of modest competence can beat LLMs.
  • jackblemming 19 hours ago
    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 ;)

    • utopcell 9 hours ago
      Let's be honest: you don't have the slightest idea about what you're talking about.
      • jackblemming 8 hours ago
        TensorFlow lost because it’s an inferior API and dev UX. Hate to break it to you.

        I’m sure it got Jeff a lot of high-fives because it’s very complicated though!

  • benzguo 21 hours ago
    loved this so much i made a jeff dean persona for my AI: https://www.zo.computer/pub/persona/prs_WtLmiGHQmHqaMKIy
  • lookingdesk 21 hours ago
    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.
    • chubot 20 hours ago
      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 19 hours ago
      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?
      • utopcell 9 hours ago
        you are not misremembering.
    • whynotminot 21 hours ago
      As far as I can tell, no one seems to think much of value was lost.
      • keeganpoppen 20 hours ago
        even at the time that was the verdict
      • foolfoolz 20 hours ago
        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
        • jll29 14 hours ago
          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.)

        • dsr_ 20 hours ago
          ... And then they didn't!
          • asadm 11 hours ago
            for good reasons.
      • shadowgovt 20 hours ago
        It turns out when you usher the dissenters out of the room, you hear a lot less dissent.
        • whynotminot 20 hours ago
          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 19 hours ago
            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.

    • lemoncucumber 19 hours ago
      That incident was the first time I ever heard of Jeff Dean and remains the main thing I associate him with.
      • scottyah 19 hours ago
        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 14 hours ago
        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?

    • morcus 20 hours ago
      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?

    • tehjoker 10 hours ago
      reading about this incident years later, i gotta say, dang Gebru was right on a lot of things

      https://www.technologyreview.com/2020/12/04/1013294/google-a...

    • shemnon42 19 hours ago
      Just another Jeff Dean optimizing out unneeded code story.