LH0ezVT
@LH0ezVT@sh.itjust.works
- Comment on Based on a true story 1 week ago:
It’s been a few years, but I’ll try to remember.
Usually, your CPU can address pages (chunks of memory that are assigned to a program) in 4KiB steps. So when it does memory management (shuffle memory pages around, delete them, compress them, swap them to disk…), it does so in chunks of 4KiB. Now, let’s say you have a GPU that needs to store data in the memory and sometimes exchange it with the CPU. But the designers knew that it will almost always use huge textures, so they simplified their design and made it able to only access memory in 2MiB chunks. Now each time the CPU manages a chunk of memory for the GPU, it needs to take care that it always lands on a multiple of 2MiB.
If you take fragmentation into account, this leads to all kinds of funny issues. You can get gaps in you memory, because you need to “skip ahead” to the next 2MiB border, or you have a free memory area that is large enough, but does not align to 2KiB…
And it gets even funnier if you have several different devices that have several different alignment requirements. Just one of those neat real-life quirks that can make your nice, clean, theoretical results invalid.
- Comment on Based on a true story 1 week ago:
No, not really. This is from the perspective of a developer/engineer, not an end user. I spent 6 months trying to make $product from $company both cheaper and more robust.
In car terms, you don’t have to optimize or even be aware of the injection timings just to drive your car around.
Æcktshually, Windows or any other OS would have similar issues, because the underlying computer science problems are probably practically impossible to solve in an optimal way.
- Comment on Based on a true story 1 week ago:
Get a nice cup of tea and calm down. I literally never said or implied any of that. Why do you feel that you need to personally attack me in particular?
For the record, I am well aware that the state of embedded system security is an absolute joke and I’m waiting for the day when it all finally halts and catches fire. But that was just not the topic of this work. My work was efficient memory management under a lot of (specific) constraints, not memory safety.
Also, the root problem is NP-hard, so good luck finding a universal solution that works within real-life resource (chip space, power, price…) limits.
- Comment on Based on a true story 1 week ago:
Except that the degree I did this for was in electrical engineering :(
- Submitted 1 week ago to science_memes@mander.xyz | 30 comments
- Comment on Anon is an anthropologist 1 month ago:
Let’s carve our memes into stone and bury them for future archaeologists.
- Comment on Anon is an anthropologist 1 month ago:
Around 10k years before us, we developed from hunter-gatherer cavemen to neolithic city builders with irrigated farms, organized religion and and a feudal society in like 1000 years. That is also pretty quick. Sure, pyramids took a bit longer. But while pyramids are pretty damn impressive, no pyramids does not mean an “uncivilized” society.
- Comment on Anon is an anthropologist 1 month ago:
But isn’t that what genres like cyberpunk do? Technological progress (A(G)I, biotech, body modifications, true VR, you name it), but society is even shittier than now? Sure, it is to some degree a cautious tale, but I feel there are quite a lot of near-future hard-ish scifi visions around