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in response to the unfortunately flagged sibling comment, the planned vaguely-rio-like windowing system for yeso is called wercam, but there is only a prototype implementation of it in the repo so far i decided that probably write() and read() is not a good way to send a large volume of pixels to the display hardware because, say, 2048×1080 32bpp at 60Hz is 530 megabytes a second, and that's a significant fraction of typical bandwidths to main memory, so it is important to strictly minimize the number of memory copies. indeed, even today, i think this is a primary driving concern in the design of usably efficient graphics systems if you write() some pixel data to a socket, the semantics of write() imply that you can overwrite it (for example with the next frame) as soon as write() returns; and the semantics of read() mean that the pixel data read from the socket by the display server needs to get put in the display server's memory space at a buffer aligned where the display server allocated the buffer. moreover, if the pixel data is intermixed in the same byte stream with control and framing data (such as the w×h dimensions of the following chunk of pixel data, for example) that will also tend to misalign it so wercam allocates the pixel data in shared memory, on unix in the form of a memory-mapped file, and then transfers the ownership of the shared memory space from the drawing application to the display server — ideally this would be done in such a way that the display server automatically knows that the drawing application cannot continue overwriting it, but on unix that is impossible, so they share access. when the display server is done with the pixel data buffer, it returns it to the drawing application for reuse writing this, though, i am struck by the realization that you can probably avoid the extra memory copy with write() and read() by the simple expedient of allocating the write() and read() buffers at page boundaries and in multiples of the page size, so that a sufficiently smart kernel can handle write() by marking the written pages copy-on-write rather than actually copying the data, and handle read() by adding a (copy-on-write) mapping for the same pages to the receiving process's address space. then the misalignment induced by the control and framing data is inconsequential, and possibly even helpful, if the framing data is a multiple of the cache line size and potential simd register size, so that the pixel data is cache-line aligned and less likely to create cache contention with whatever framebuffer the display server eventually copies it into — ⁂ — as for moving to argentina, it's a good idea to have officially certified copies, made within the last year, of all your immigration-relevant documents; apostilles for those documents; a lot of money, ideally in bitcoin or 100-us-dollar bills (smaller bills and the old bills with a smaller benjamin franklin face trade at a discount, and bitcoin trades at a wide spread); fluency in spanish; a small number of easily salable electronic gadgets that you nevertheless actually use, such as macbooks, iphones, and recent phones or tablets from xiaomi, samsung, or motorola (compatible with the frequency bands we use here!), along with powerbanks and bluetooth earbuds; and enough of your savings to live on the form of 18-karat gold jewelry worn under your clothes you can't legally bring pepper spray on the plane, but you should probably buy some as soon as you arrive. expect to get robbed about once a week during the first part of your stay, including from your checked luggage before you arrive, so don't be too attached to your possessions withdrawing money from a dollar bank account at argentine atms does work but you only get about 45% of the money you withdraw thanks to the fake exchange rate; some expats have reported success in sending themselves money with western union, which doesn't use the fake exchange rate, but only scales up to about 200 dollars at a time, and may trigger investigations by the tax authorities because voip on cell data is illegal, voip accounts from companies with a nexus in argentina will not work, at least on cellphone data (which is quite cheap, but i think signing up for a cellphone line will require an argentine citizen or permanent resident to vouch for you). this means google fi doesn't work at all, but for example voip.ms works fine with sipphone, and so does jitsi. also most cafes, restaurants, hotels, etc., have free wifi for customers, secured with a wpa psk key that changes every year or two once you have a place to live that isn't a hotel or hostel, leave your passport there so that if you get robbed at least you won't lose your passport. unless armed robbers escort you at knifepoint to your house and demand entry in order to loot your house, which is a thing that happened to a couple of friends of mine. still you can probably hide your passport somewhere that they won't find it, and tell them that you lost it and are waiting for a replacement if they ask. a usa driver's license is generally enough to satisfy cops who demand to see your papers, and in 17 years that has happened to me only once, while i've been robbed on the street several times don't expect to get a job! we're in the middle of the worst economic crisis we've had since 02001, so you'll probably have to live off your savings (or earnings from working for overseas clients) indefinitely; also keep in mind that living in the middle of an economic crisis can be depressing and anxiety-inducing, which can exacerbate any mental health problems you may have stay out of the villas and la boca |
if you're trying to do something else on the computer, even on a different core, that's bottlenecked on memory bandwidth (as opposed to cpu or i/o or something) that's like using 50% of the computer, which means the whole computer is effectively half as fast
i think it's worth a significant amount of complexity to get your display system to suck up 30% of your computer instead of 50%, even when you're doing something that updates the full screen every frame, such as smooth scrolling, a 3d fps, or watching a movie, and that's why I think it's important to try to minimize copies in the pixel paper path
also keep in mind that many people dual-wield monitors these days, and 3840x2160, though common, is not as big as they get