seppel

Schengen has independent of the EU status. Eg. you can move freely from Germany to Switzerland (without obligatory border check) but not between Germany and EU-member Cyprus (there is the obligatory border check).

> They could not be making any money on advertising there, I assume?

When they show an advertisement of, say, some asian company to a russian user, they are still making money, aren't they?

> but its rarely gb at the same time. Thats the point. Its a dumping ground for stuff thats not used very often.

But it has to be GB to actually make a difference. If your swap is not full of GB of data, then obviously you don't need it (or it just becomes a reserve when you are in an OOM situation - but this is where you don't want to be with swap avaible either)

Firefox (and I guess Chrome as well) throws aways memory of unused tabs.

> What if I don't have no more free DIMM slots but I already have 1 TiB NVMe and I am fine with my workload being finished slightly (or even noticeably) slower as opposed to not being able to do at all?

Then you obviously have a workload where having swap make sense (and you could even add swap on the fly in such a case). But that is not typical at all.

> Given that the author works at a large company, that has millions of machines, and where any swap change has cost implications in the tens of millions pounds, I suspect the article is based on data, rather than vibes.

Yes, but the author is most likely optimizing for a metric that I don't care so much in my per personal computer while dismissing metrics that I care about.

> It was always the case. but then a TB of disk isn't that expensive anymore.

But swapping out GB of RAM is expensive in terms of latency.

> Swapping 32GB of memory in and out of an NVMe SSD is much faster than swapping 1GB out of a spinning disk so I really don't get that argument.

This is true, but it still takes time. What kind of workload do you have where you swap out 32GB of RAM? If you are in this situation you almost certainly need to buy these additional 32GB of RAM.

This reads like something from the 90s. Buy whatever you think you need as swap as "more RAM" and call it a day. I'm running my desktop Linux without swap since maybe 20 years, and I never had any of this "pathological behaviour at near-OOM" afterwards.

And I have time to think about better problems than "You can achieve better swap behaviour under memory pressure and prevent thrashing by utilising memory.low and friends in cgroup v2."

The core problem with swap is that nowadays you need gigabytes of swap to actually make a difference (when you have 32GB of RAM, 1GB of swap is 1/32 of a difference). And you certainly don't want to system to swap in and out gigabytes of memory.

What I wrote was a bit unclear: They want to avoid that you buy a low cost ticket and resell it to somebody else a day before the flight (because you either cannot make it or because you want to make money).

The do that so that you can't resell your ticket.

The "your username/password is wrong" message came in a timely manner. So someone transformed "some unforeseen error" into a clear but wrong error message.

And this caused a lot of extra trouble on top of the incident.

> That said, getting there strikes me as pretty challenging. Automatically detecting a down state is difficult and any detection is inevitably both error-prone and only works for things people have thought of to check for. The more complex the systems in question, the greater the odds of things going haywire. At Meta's scale, that is likely to be nearly a daily event.

Well, in principle, the frontend just has to distinguish between HTTP status 500 (something broken in the backend, not the fault of the user) and some HTTP status code 4xx (the user did something wrong).

> If 0.01% of the transactions a bank processes daily need some form of human intervention

Then these transactions will be delayed anyway. You could still process 99.99% of the transactions on Sunday.

Visa, Mastercard, Paypal as operate 24/7. ATMs operate 24/7. Neo banks allow intra-bank transfers 24/7. And they deal with the fraud and AML stuff.

X86 has ENDBR32 and ENDBR64 (end branch) for this.