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lclarkmichalek

2,734 karma · joined May 2, 2011

PE @ FB

Contact: lclarkmichalek@gmail.com, lcm@fb.com

[ my public key: https://keybase.io/laurie; my proof: https://keybase.io/laurie/sigs/ZcNOTg2PcOt9Sp6SZg-O788Dp1AAIzNLE9JWmMhGkZI ]

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lclarkmichalek··on GAO: DOE Is Prematurely Excluding Less Expensive Options for Nuclear Cleanup
Isn’t it a fairly natural (and useful) capitalist outcome that as prices rise incentives to increase supply increase? What’s technocratic about responding to a demand change?
lclarkmichalek··on The silent death of good code
Hilarious. The code being produced previously was crap - it was just your crap. Baseline agents produce something similar, but can at least be guided, durably, towards producing less crap code.
lclarkmichalek··on Amazon strategised about keeping water use secret
In absolute terms, yep. In marginal terms, not so much. See also: paradox of value
lclarkmichalek··on US probes Waymo robotaxis over school bus safety
Highways are pretty safe. The road is designed from start to finish to minimise the harm from collisions. That’s not true of urban streets
lclarkmichalek··on EU court rules nuclear energy is clean energy
I think if you regulated coal on a linear no threshold risk model, you'd find the costs to be somewhat closer.
lclarkmichalek··on 2025 Infrastructure Report Card
There's also the converse argument, to governments that look to infrastructure as the secret to all prosperity - America succeeds without infrastructure, somehow.
lclarkmichalek··on Mark Cuban offers to fund former 18F employees
Natural monopolies exist, for sure. Your insurance example is odd though - insurance markets are generally highly competitive. The recent cases where we’ve seen a loss of competition in the market (CA home insurance, for example) have been driven by regulators imposing price controls.

The issue with healthcare is that providers have leverage over insurers, not that there is a lack of competition for insurance.

lclarkmichalek··on Systems ideas that sound good but almost never work
The usual issue is the addition of control loops without much understanding of the signals (CPU utilization is a fun one), and the addition of control loops without the consideration of other control loops. For example, you might find that your cross region load balancer gets into a fight with your in-process load shedding, because the load balancer's signals do not account for load shedding (or the way they account for the load shedding is inaccurate). Other issues might be the addition of control loops to optimize service local outcomes, to the detriment of global outcomes.

My general take is that you want relatively few control loops, in positions of high leverage.

lclarkmichalek··on Netflix buffering issues: Boxing fans complain about Jake Paul vs. Mike Tyson
What does this have to do with the topic being discussed?
lclarkmichalek··on The perils of transition to 64-bit time_t
There is a limit on reliable usage of the FS. Call it what you want. The user doesn't particularly care.
lclarkmichalek··on The perils of transition to 64-bit time_t
It does happen in prod. Usually due to virtual FSes that rely on get_next_ino: https://lkml.org/lkml/2020/7/13/1078
lclarkmichalek··on Bento: Jupyter Notebooks at Meta
I think a fair few of them were created because they knew a bit too much about FOQS
lclarkmichalek··on Launch HN: Fortress (YC S24) – Database platform for multi-tenant SaaS
You rather explained the value prop of this product then. The benefits of isolation without the 1 business day wait.
lclarkmichalek··on Launch HN: Fortress (YC S24) – Database platform for multi-tenant SaaS
Personally, there's no way I'd want a customer initiated operation to trigger something like terraform or mess with DB schemas. On the security side, it would significantly complicate the permissions structure from the application to the database. And on the performance side, I have absolutely no mental model for how operations like that scale, and how trivial of a DoS I'm exposing myself to. At the same time, I love the isolation (mostly operationally, the security & privacy side is also nice) that db-per-customer would bring. If this product helps bridge the gap, then it sounds good to me.
lclarkmichalek··on Will we have a negative leap second? [pdf] (2022)
Doesn’t astronomy already use TAI, which has no leap seconds?
lclarkmichalek··on American drivers even more distracted by phones. Pedestrian deaths are soaring
Penalties for being on your phone while driving are fairly different between different countries. In the UK it's 6 points and £200 if you're caught. It's a fair deterrent
lclarkmichalek··on Power grab: the hidden costs of Ireland's datacentre boom
The impact on the energy market always seems a tad misstated in these articles. Datacenters are often funded through corporate power purchase agreements, committing them to purchasing power directly from the generator over periods of multiple years. Those CPPAs are often tied to the development of new renewable energy generation (ex: https://www.matheson.com/insights/detail/matheson-advises-br...). Now, that still puts pressure on the grid for transmission, raises the marginal cost of renewable energy, and in cases where the generator cannot meet demand, presumably increases demand on other generation sources. But it makes the “40% of energy being used by DCs” stat seem a little misleading - a reasonable amount of generation exists because of these DCs.

(I work for Meta, who’s Clonee datacenter is mentioned in this article)

lclarkmichalek··on Pkl, a Programming Language for Configuration
Never used Bazel in my life, so while I can appreciate your passion, I guess I don't share your perspective. Generally the pattern I've seen has been providing a skylark interface to allow folks to define rules or configurations, which are then consumed through by whatever service via starlark-rust or similar implementations.
lclarkmichalek··on Pkl, a Programming Language for Configuration
In a competition with sky/starlark, I feel skylark would win here. “Safe subset of python” is what a lot of people presented with this problem want, and skylark gives them almost exactly that.

OTOH, curious to see what advantages Pkl gains from not having the constraints of maintaining familiarity with another language.

lclarkmichalek··on Retries – An interactive study of request retry methods
I mean, they can and should be both. Local decisions can be cheap, and very simple to implement. But global decisions can be smarter, and more predictable. In my experience, it's incredibly hard to make good decisions in pathological situations locally, as you often don't know you're in a pathological situation with only local data. But local data is often enough to "do less harm" :)
lclarkmichalek··on Retries – An interactive study of request retry methods
This still isn't what I'd call "safe". Retries are amazing at supporting clients in handling temporary issues, but horrible for helping them deal with consistently overloaded servers. While jitter & exponential backoff help with the timing, they don't reduce the overall load sent to the service.

The next step is usually local circuit breakers. The two easiest to implement are terminating the request if the error rate to the service over the last <window> is greater than x%, and terminating the request (or disabling retries) if the % of requests that are retries over the last <window> is greater than x%.

i.e. don't bother sending a request if 70% of requests have errored in the last minute, and don't bother retrying if 50% of the requests we've sent in the last minute have already been retries.

Google SRE book describes lots of other basic techniques to make retries safe.

lclarkmichalek··on Farewell EC2-Classic, it’s been swell
I wonder why they didn't do that in the 14 years since VPCs were introduced?
lclarkmichalek··on Big Tech as the New Big Tobacco
Bronze age collapse wasn't exactly great though.
lclarkmichalek··on OpenWorm – A computational model of C. elegans worm
It models wiggling forward. It models wiggling backwards. And occasionally it models fucking itself. That’s it.
lclarkmichalek··on California AG and state senators introduce bill to ban hidden fees
Unbundling is a real thing, with some pronounced second order affects. The first order effect of charging for in flight food service and checked bagged is purely redistributive, but rise of low cost, heavily unbundled airlines has increased the total market for air travel, increasing net economic activity in the sector.
lclarkmichalek··on Tesla’s Dojo Microarchitecture
Setting up a hardware platform of this kind that is useable in production costs significantly more than a couple of million
lclarkmichalek··on Dragonflydb – A modern replacement for Redis and Memcached
There are also things that are unmitigated improvements.
lclarkmichalek··on Meta quickly detects silent data corruptions at scale
A bit before my time, but maybe a physical capacity order, to a non fungible pool. The infra is quite different now (mostly to avoid this kind of inefficiency)
lclarkmichalek··on Meta quickly detects silent data corruptions at scale
I mean, that's not true in the general case. That'd be incredibly wasteful.

(Work at Meta, mostly on capacity)

lclarkmichalek··on Run Ordinary Rails Apps Globally (2021)
There are an incredible number of websites that have incredible read:write ratios. I would suggest doing everything you can to avoid writing to the database on every request.
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