DaPorkchop_ @ DaPorkchop_ @lemmy.ml

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2 yr. ago

Since you haven't explained how this helped you find your wife, I have to assume that you built one and aimed it at random people on the street while making sex noises like some kind of high-precision mating call.

[citation needed]

The Penguins of Madagascar is much older than Top Gun: Maverick, how could it the show have referenced a movie from the future? Or did the original commenter mean the original Top Gun?

I was thinking it's from The Penguins of Madagascar, Skipper says "just smile and wave, boys, smile and wave" practically once per episode.

That's ~2.4Gbit/s. There are multiple residential ISPs in my area offering 10Gbit/s up for around $40/month, so even if we assume the bandwidth is significantly oversubscribed a single cheap residential internet plan should be able to handle that bandwidth no problem (let alone a for a datacenter setup which probably has 100Gbit/s links or faster)

50MB/s is like 0.4Gbit/s. Idk where you are, but in Switzerland you can get a symmetric 10Gbit/s fiber link for like 40 bucks a month as a residential customer. Considering 100Gbit/s and even 400Gbit/s links are already widely deployed in datacenter environments, 300MB/s (or 2.4Gbit/s) could easily be handled even by a single machine (especially since the workload basically consists of serving static files).

I think there are definitely some specific cases where it makes sense. For example garbage dumps (and compost facilities as well, I think) produce tons of methane and other unpleasant flammable gases which often get flared off, it seems only reasonable that if you're gonna be burning the gas anyway that you might as well use that heat to spin a turbine instead of just fuelling a uselessly burning flame on a pole.

In theory biofuel is perfectly carbon-neutral if you're growing all the input biomass yourself, since all the carbon released when the fuel is burned is carbon which was captured during the growth stage. But in practice it's not ideal:

• There's still plenty of potential sources of emissions, like harvesting and transporting the biomass will likely be burning fossil fuels and also tires and stuff
• Growing biomass is slow, so from what I understand a lot of it ends up coming from newly cut trees and stuff because it's cheaper than buying tons of land, planting stuff and then waiting years for stuff to grow
• IMO the main problem: there are other more useful things we could be doing with that land, if you can grow crops for biofuel production you could also just grow food there and put some wind turbines or solar panels or something on one of the many places on earth not suitable for agriculture to provide the energy

If the biofuel is being produced from like agricultural byproducts (e.g. the stalks of harvested crops) I don't think there's really a problem, but AFAIK most of that stuff gets used for compost or gets left on fields to put nutrients back in the soil (and because it's cheaper and easier to leave it than having to collect it again).

Eh, I'd say R2-D2 doesn't count as a "man" at all, being neither human nor clearly gendered in any way.

I never imagined I'd ever see someone compare Mr. Rogers to drugs, but here we are.

I've got an old HP laptop which I've been running a Jenkins server on for years. The fan died back in like 2018, and I just kept putting off buying a replacement, so it has been running with no fan for 7 years now. Remarkably it still works fine, although a but slower than it used to thanks to thermal throttling :P

Roscoe is one of my professors at ETH, and he gave a keynote at VISCon a few months ago where he discussed this stuff and what his department is working on. Apparently a lot of their (they being the systems department at ETH) current work is related to formally modeling which parts of a system have access to what other parts, and then figuring out which of those permissions are actually needed and then deriving the strictest possible MPU configuration while still having a working system. The advantage of this approach over an entirely new kernel is that, well, it doesn't require an entirely new kernel, but can be built into an existing system, while still allowing them to basically eliminate the entire class of vulnerabilities they're targeting.

This guy (Roscoe) is one of my professors and I've heard him give a few talks related to this before, so I'll try to summarize the problem:

Basically, modern systems do not really match with the classic model of "there's a some memory and perhipheral devices attached to a bus, and they're all driven by the CPU running a kernel which is responsible for controlling everything". Practically every component has it's own memory and processor(s), each running their own software independently of the main kernel (sometime even with their own separate kernel!), there are separate buses completely inaccessible to the CPU specifically for communicating between components, often virtually every component is directly attached to the memory bus and therefore bypasses the CPU's memory protection mechanisms, and a lot of these hidden coprocessors are completely undocumented. A modern smartphone SoC can have 10s of separate processors all running their own software independently of each other.

This is bad for a lot of reasons, most importantly that it becomes basically impossible to reason about the correctness or security of the system when the "OS kernel" is actually just one of many equally privileged devices sharing the same bus. An example of what this allows: it is (or was) possible to send malformed WiFi packets and trigger a buffer overrun in certain mobile WiFi modems, allowing an attacker to get arbitrary code execution on the modem and then use that to overwrite the linux kernel in main memory, thus achieving full kernel-level RCE with no user interaction required. You can have the most security-hardened linux kernel you want, but that doesn't mean a damn thing if any one of dozens of other processors can just... overwrite your code or read sensitive data directly from applications!

As I understand it, the goal of these projects is basically to make the kernel truly control all the hardware again, by having them also provide the firmware/control software for every component in the system. Obviously this requires a very different approach than conventional kernel designs, which basically just assume they rule the machine.

This is specific to page reclamations, which only occur when the kernel is removing a block of memory from a process. VMs in particular pretty much never do this; they pin a whole ton of memory and leave it entirely up to the guest OS to manage. The JVM also rarely ever returns heap memory to the kernel - only a few garbage collectors even support doing so (and support is relatively recent), and even if you have it configured correctly it'll only release memory when the Java application is relatively idle (so the performance hit isn't noticeable).

Yeah, it'd definitely be faster while pages are actively being moved to swap.

This probably won't make much difference unless your application is frequently adding and removing large numbers of page mappings (either because it's explicitly unmapping memory segments, or because pages are constantly being swapped in and out due to low system memory). I would suspect that the only things which would really benefit from this under "normal" circumstances are some particularly I/O intensive applications with lots of large memory mappings (e.g. some webservers, some BitTorrent clients), or applications which are frequently allocating and deallocating huge slabs of memory.

There might be some improvement during application startup as all the code+data pages are mapped in and the memory allocator's arenas fill up, but as far as I know anonymous mappings are typically filled in one page at a time on first write so I don't know how relevant this sort of batching might be.

Jolkien Rolkien Rolkien Tolkien

Yes, I will store the expensive paintings in a house made of toothpicks and cardboard with a tar roof in a state known to have widespread fires every year. It is a good idea.

Am I gregnant?

I don't know about the others, but Arduino is literally just C++ with some macros/library functions.

My confusion isn't why they're decorated, but why the decoration is always on the downwards facing side so you can't actually see it once installed.