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).
EEA gives you that, and Iceland is a member state of that too. So Iceland already enjoys this freedom.
I think Switzerland has a bilateral agreement with the EU (or via EFTA) that allows for free movement and employment of people, so they enjoy these freedom as well despite neither being in the EU nor the EEA (but they are a member of EFTA).
Yeah, I don’t know about what is included in the bilateral agreement with Switzerland. But at least in EEA (which is EU + EFTA - Switzerland) you are free to work in any of the member states.
The person you are replying said "moving" as in you relocate to another country. Not going on vacation. Swiss people can not just move to say denmark one day and start working there. They need work visas etc for that.
Switzerland is both a member of Schengen (meaning no border checks) and its nationals enjoy FoM (via bilateral arrangements). They don't need work visas.
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.
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.
Swap is less critical now, and given that k8s has some pathological dislike of it (again I suspect based on vibes) I can see why people dont have it.
However when you are using close to 70% of your total ram, swap improves performance significantly. Also where I work, it also stop the OOM from killing my repo VFS layer when I'm compiling something.
> The core problem with swap is that nowadays you need gigabytes of swap to actually make a difference
It was always the case. but then a TB of disk isn't that expensive anymore.
> 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.
but its rarely gb at the same time. Thats the point. Its a dumping ground for stuff thats not used very often. meaning that you can have a bigger VFS cache, which reduces latency
> 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)
> > 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)
I think the parent meant, that it barely needs to be read / write GBs at the same time. Not that that much swap is never being in use at the same time.
So you can use a lot of swap, but will never need to read it back in all at once.
I have stopped using swap on any computers, laptops, desktops or servers, more than 2 decades ago.
At that time, removing the swap was definitely a great improvement (with the condition of having installed enough real memory in the computers; but even with insufficient memory it was much better to have a few processes killed instead of having an unusable computer that had to be forcefully rebooted, losing everything that had not been already saved).
Perhaps the handling of swap has been improved meanwhile and in certain unusual niche environments having swap might provide some benefits.
Nevertheless, I doubt very much that this is true. I have never seen any such case where swap could have been useful.
When there is enough memory, there should be no writes to the swap, because such writes can only diminish the performance, and in an unpredictable way, because they can trigger the SSD garbage collector. If there are no writes to the swap, there is no reason for it to exist. If there isn't enough memory, the cheapest solution is to buy more memory, instead of trying to find a software workaround for that.
The memory pages that are not dirty can always be discarded by the operating system and read again later from the SSD if needed. No swap is needed for that. There exists no way in which swap can improve performance in comparison with having enough memory. Having to also discard dirty pages is just another way of saying that there isn't enough memory and you are willing to degrade the performance instead of paying for enough memory.
Swap memory is certainly never needed in personal computers, outside of temporary use in certain exceptional situations, when one would be willing to run very slowly a program that does not fit in the memory, due to lack of access to a computer with more memory.
Swap could be useful only when configured in a great number of servers that run a well characterized workload, where one could make a trade-off between application performance and total memory cost.
In a server environment you don't have the luxury of running your 4 GB needing app on a 128 GB machine - that means you have overprovissioned and are paying a stupid tax.
A modern server aims to run as close as possible to 100% CPU and RAM usage.
In those cases you need swap to kick out rarely used memory (initialization, ...)
> 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.
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?
As an example of such workload: a server, one of the many, that runs financial calculations from many web users. It's fine for it to become somewhat slower: we'll notice the performance degradation in the metrics and stop accepting new connections for a while. It is not fine for it to just die with OOM ― the users automatically will reconnect to other servers, leading to a sort of a thundering herd scenario.
> 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.
Where did I say anything about swapping out entire 32GB? Why does everything need to be binary in this argument? As in you either swap 32GB or have swap disabled?
What if you from time to time you only swap a couple of GB? Isn't that better than having your system completely lock up and need rebooting?
Why? Have you actually looked at the numbers and did the math, or are you scared out of FUD and think the sky is falling every time write calls are made to the SSD?
I treat my 1TB SSD like a loaner and after doing the math, based on my write patterns in the last 2 years, the SSD should wear out in about ..checks notes.. 12 years. I'm a lot more likely to replace it 2-4 years though to upgrade to a bigger and faster model anyway.
Plus, all storage dies eventually, that's why backups are important. You paid for it, you might as well make the most use of it while it lasts instead of trying to "hypermile it" since you won't be leaving it as inheritance to your grandchildren.
But we don't live in legacy times we live in present times. So is it too much to expect people on a tech forum to be at least a bit up to date on the present tech instead of regurgitating fears 10 years out of date?
If you're wearing out your SSD life endurance in a few years, you have an issue.
Yeah the only reason I've ever needed swap was to compile chonk cpp packages on SBC systems that simply don't have enough ram to load it all. With swap it works fine, otherwise the system just freezes entirely. Despite what OP claims, emergency memory is literally the only case I've ever had for it over the years. On desktop buying more ram is trivial.
Yeah. Some of the reasons on that list are debatable
I think swap is useful as a temporary memory overflow area, but that's it. Actually "running relying on swap" is harmful
Items 1 and 2 on the list sound like fiction. Item 4 sounds plausible (same for the Windows 9X series - sigh - where cache and swap would allegedly fight each other)
I always assumed that scanning a boarding pass means it's marked as "used" and would flag up if scanned again. Or at the very least, previous scans would immediately show up so the attendant can verify.
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).
As is OSL / Oslo Gardermoen, but on occasion they will use the PA to find late pax, at least on international flights. Presumably there's more paperwork if there's a no-show, I don't know.
Anyway, sitting in a bar there a few years ago, waiting for my flight, I hear a series of progressively more strongly worded announcements for pax X and Y to get to the gate or else.
Noone shows. Then the 'This is absolutely, positively, make no mistake about it final call for flight such-and-such, gate closes in 30 seconds.'-announcement.
At which point the two men at the table next to me get up and stroll over to the nearmost gate.
I almost fist-pumped when the gate attendant just looked at them (eyes ablaze!) and said 'Sorry, gate just closed!' then proceeded to inform whoever was listening on the VHF that pax X and Y were no-shows, presumably to have their luggage located and offloaded.
I once was one of 10 unrelated paxes that missed their flight because announcements were very quiet and boarding window was very short. Not sure whether 10% of the flight manifest were all entitled or the gate attendant was mean.
Indeed! Just a quick question to satisfy my curiosity - seeing as you fly out of Trondheim, work with embedded systems and have a background in physics, would you happen to be named Jostein and have a dark past frequenting Omega Verksted and occasionally also Akademisk Radioklubb c. 2000?
> 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).
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.
The EU is showning these banners on their own websites. So not even the EU is capable of creating a website without banners (because - even the EU - wants analytics and other bullshit).
The EU parliament website says "We use analytics cookies to offer you a better browsing experience. You have the choice to refuse or accept them." I'd personally rather have the choice than not.
> And you clearly want to carry 3000+ EUR in your pocket than paying by card? Europe is safe, but I will definitely not walk around with that much cash on my person.
I'd also rather pay the Macbook by card due to practicality, but I don't understand your second sentence. Why would you walk around with a Macbook worth 3k but not with 3k in cash? Nobody knows that you have 3k in cash with you, whereas everybody can see you walking out of the Apple Store with the Macbook.
