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Why is everything so scalable?

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Re: Why is everything so scalable?

#81

Post by williamdclt »

DrScientist wrote: post #27

Isn't it simple as the following? Break your code into modules/components that have a defined interface between them. That interface only passes data - not code with behaviour - and signal the method calls may fail to complete ( ie throw exceptions ). ie the interface could be a network call in the future. Allow easy swapping of interface implementations by passing them into constructors/ using factories or dependenc…

You're not missing something, but you're assuming that it's easy to know ahead of time where the module boundaries should be and what the interfaces should look like. This is very far from easy, if possible at all (eg google "abstraction boundaries are optimization boundaries").

Also, most of these interfaces you'll likely never need. It's a cost of initial development, and the indirection is a cost on maintainability of your code. It's probably (although not certainly) cheaper to refactor to introduce interfaces as needed, rather than always anticipate a need that might never come.

Re: Why is everything so scalable?

#82

Post by ben_w »

phkahler wrote: post #75
ben_w wrote: post #52

Earlier quoted context omitted.

This is probably also true for 98% of startups. I think most people don't realise that "10 million" records is small, for a computer. (That said, I have had to deal with code that included an O(n^2) de-duplication where the test data had n ~= 20,000, causing app startup to take 20 minutes; the other developer insisted there was no possible way to speed this up, later that day I found the problem, asked the CTO if the…

I thought you were going to say to reduced O(n^2) to O(n*log(n)), but you just deleted the operation. Normally I'd say that's great, but just how much duplicate data is being left around now? Is that OK?

Each element was about, oh I can't remember exactly, perhaps 50 bytes? It wasn't a constant value, there could in theory be a string in there, but those needed to be added manually and when you have 20,000 of them, nobody would.

Also, it was overwhelmingly likely that none of the elements were duplicates in the first place, and the few exceptions were probably exactly one duplicate.

Re: Why is everything so scalable?

#83

Post by pigcat »

My friend is the first dev hire at a startup where they prematurely overengineered for scalability. The technical founders had recently exited a previous startup and their rationale was that it makes a future acquisition easier, since a potential acquirer will weigh scalability in their evaluation of the code (and maybe even conflate it with quality). In fact it was a regret from their first startup that they hadn't baked in scalability earlier. I remain skeptical of the decision, but curious if there's any truth to the fact that acquirers weigh scalability in their scorecard?

Re: Why is everything so scalable?

#85

Post by llm_nerd »

crazygringo wrote: post #60
llm_nerd wrote: post #46

Earlier quoted context omitted.

>Empirically, that does not seem to be the case. Failures are astonishingly, vanishingly rare. Like it's amazing at this point how reliable almost every system is. There are a tiny number of failures at enormous scale operations (almost always due to network misconfigurations, FWIW), but in the grand scheme of things we've architected an outrageously reliable set of platforms. >That's not scaling, just redundancy. In…

> Failures are astonishingly, vanishingly rare You and I must be using different sites and different clouds. There's a reason isitdownrightnow.com exists. And why HN'ers are always complaining about service status pages being hosted on the same services. By your logic, AWS and Azure should fail once in a millennium, yet they regularly bring down large chunks of the internet. Literally last week: https://cyberpress.or…

[flagged]

Re: Why is everything so scalable?

#86

Post by phkahler »

ben_w wrote: post #69
jwr wrote: post #5

I don't get this scalability craze either. Computers are stupid fast these days and unless you are doing something silly, it's difficult to run into CPU speed limitations. I've been running a SaaS for 10 years now. Initially on a single server, after a couple of years moved to a distributed database (RethinkDB) and a 3-server setup, not for "scalability" but to get redundancy and prevent data loss. Haven't felt a nee…

> unless you are doing something silly, it's difficult to run into CPU speed limitations. Yes, but it's not difficult to do something silly without even noticing until too late. Implicitly (and unintentionally) calling something with the wrong big-O, for example. That said, anyone know what's up with the slow deletion of Safari history? Clearly O(n), but as shown in this blog post still only deleted at a rate of 22 i…

>> Yes, but it's not difficult to do something silly without even noticing until too late. Implicitly (and unintentionally) calling something with the wrong big-O, for example.

On a non-scalable system you're going to notice that big-O problem and correct it quickly. On a scalable system you're not going to notice it until you get your AWS bill.

Re: Why is everything so scalable?

#87

Post by sgarland »

llm_nerd wrote: post #16

This piece is written with a pretty cliche dismissive tone that assumes that everything everyone else does is driven by cargo-culting if not outright ignorance. That people make these choices because they're just rushing to chase the latest trend. They're just trying to be cool, you see. Here's the thing, though: Almost every choice that leads to scalability also leads to reliability. These two patterns are effective…

A distributed monolith - which is what nearly all places claiming to run microservices actually have - has N^m uptime.

Even if you do truly have a microservices architecture, you’ve also now introduced a great deal of complexity, and unless you have some extremely competent infra / SRE folk on staff, that’s going to bite you. I have seen this over and over and over again.

People make these choices because they don’t understand computing fundamentals, let alone distributed systems, but the Medium blogs and ChatGPT have assured them that they do.

Re: Why is everything so scalable?

#88

Post by potatolicious »

nicoburns wrote: post #18
yobbo wrote: post #10

Many startup business models have no chance of becoming profitable unless they reach a certain scale, but they might have less than 1% probability of reaching that scale. Making it scalable is easy work since it is deterministic, but growing customers is not. Another perspective is that the defacto purpose of startups (and projects at random companies) may actually be work experience and rehearsal for the day the fou…

I guess the work is deterministic, but it often (unintentionally) makes the systems being developed non-deterministic!

Ah yes. I once worked at a startup that insisted on Mongo despite not having anywhere near the data volume for it to make any sense at all. Like, we're talking 5 orders of magnitude off of what one would reasonably expect to need a Mongo deployment.

I was but a baby engineer then, and the leads would not countenance anything as pedestrian as MySQL/Postgres.

Anyway, fast forward a bit and we were tasked with building an in-house messaging service. And at that point Mongo's eventual consistency became a roaring problem. Users would get notifications that they had a new message, and then when they tried to read it it was... well... not yet consistent.

We ended up implementing all kinds of ugly UX hacks to work around this, but really we could've run the entire thing off of sqlite on a single box and users would've been able to read messages instantaneously, so...

Re: Why is everything so scalable?

#89

Post by sgarland »

ahoka wrote: post #70
BirAdam wrote: post #29

Just to be honest for a bit here... we also should be asking what kind of scale? Quite a while ago, before containers were a thing at all, I did systems for some very large porn companies. They were doing streaming video at scale before most, and the only other people working on video at that scale were Youtube. The general setup for the largest players in that space was haproxy in front of nginx in front of several…

Are those over engineered systems even actually scalable? I know teams who designed a CQRS architecture using messages queues and a distributed NoSQL database and fail to sustain 10req/s for a read in something that is basically a CRUD application. Heck once someone literally said "But we use Kafka, why aren't we fast?!".

I watched in amusement as the architecture team at $JOB eagerly did a PoC of a distributed RDBMS, only to eventually conclude that the latency was too high. Gee… if only someone had told you that would happen when you mentioned the idea. Oh wait.

Re: Why is everything so scalable?

#90

Post by ahoka »

robertlagrant wrote: post #37
lpapez wrote: post #14

Earlier quoted context omitted.

> Are there really people out there who still reach for Meta-scale by default? Who start with microservices? Anecdotally, the last three greenfield projects I was a part of, the Architects (distinct people in every case) began the project along the lines of "let us define the microservices to handle our domains". Every one of those projects failed, in my opinion not primarily owing to bad technical decisions - but th…

I think this sounds more like Domain Driven Design than Clean Code.

It kinda started with Clean Code. I remember some old colleagues walking around with the book in their hand and deleting ten year old comments in every commit they made: "You see, we don't need that anymore, because the code describes itself". It made a generation (generations?) of software developers think that all the architectural patterns were found now, we can finally do real engineering and just have to find the one that fits for the problem at hand! Everyone asked the SOLID principles during interviews, because that's how real engineers design! I think "cargo cult" was getting used at that time too to describe this phenomenon.
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