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24-core CPU and I can’t move my mouse (2017)

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Re: 24-core CPU and I can’t move my mouse (2017)

#161

Earlier quoted context omitted.

For my own projects I use C because I know it, but also because I know and trust the ecosystem. I seem to have developed something of a software-survivalist mentality, so I like to know that I can build my project five years from now without worrying about whether some remotely-hosted dependency isn't there any more. (I'm not claiming that newer, more trendy languages necessarily fail this test - just that I don't kn…

Out of curiosity, when you considered the compilers to use for your CPU project, did you look at pcc? And if so, how would you say vbcc compares, in terms of ease of porting to a new arch?

I looked at a number of different options (http://retroramblings.net/?p=1277) but didn't spend a great deal of time looking at pcc. I was amazed to discover how many different options there were, actually!

VBCC's backend interface is well documented, which helps a lot - and there's a skeleton "generic RISC" backend which is trivial to copy and use as a starting point - I found it very useful to be able to tweak a working backend and observe how the generated code changes, while I was getting a feel for how it all hangs together.

VBCC does have an unusual license, however - commercial usage requires permission from the author.

Re: 24-core CPU and I can’t move my mouse (2017)

#162

Earlier quoted context omitted.

I agree. Windows is basically fine these days. It's even better than Mac and Linux in a big way from a desktop stability point of view because it has the Ctrl-alt-delete interface which works reliably and lets you kill the offending program. Linux has various useless options like sysreq shortcuts that you can't remember and kill random processes, and I don't think Mac has anything, though to be honest I don't recall…

I wish Ctrl+Alt+Delete would be reliable enough to work with full-screen games. But, half the time, when you try to launch Task Manager that way to kill the offending process, it ends up under the game's output. I've learned to kill processes using keyboard navigation by looking at Task Manager's thumbnail in Alt-Tab process list, but it's ridiculous that we still need to do this kind of dance in 2023.

There's a way to make it always appear above other windows. Let me see if I can find that again...

Ah, it's in the options menu on the task manager itself (alt + O to access the menu without a mouse).

Re: 24-core CPU and I can’t move my mouse (2017)

#163
post #84
post #60

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Did you check? I tell my QA people all the time: If you come to me with "I think" or "I believe", it sounds like you've got some reading to do.

I didn't write "I think" or "I believe". If you want to know my epistemic status: I know about windows based on observable surface behavior and bugs related to accelerated cursors, but I haven't looked at the source. I know about wlroots because I saw the pull requests related to that and a flag to disable it in sway. The last statement regarding other platforms was an educated guess based on gfx card history: accele…

Just an FYI-- I tried to get ChatGPT to generate a question as condescending as what you just responded to. It now generally refuses to write anything impolite.

The most I could get was to ask it to take an avuncular tone, at which point it did ask you to "spill the beans, kiddo" about these compositors. :)

Re: 24-core CPU and I can’t move my mouse (2017)

#164

Earlier quoted context omitted.

Did they? My MacBook is much worse at multitasking. In fact the OS I've found to be best at multitasking is Debian/Ubuntu.

Switching from FF to Chrome (this was like a decade ago, to be fair to FF) eliminated about 50% of my beachballs and other unresponsiveness system-wide, not just when using FF. Switching from Chrome to Safari got rid of almost all the rest, and also made my battery life match Apple's claims. [EDIT] And when I do still run into trouble, it's almost always Electron chat apps. Slack, Teams, and Discord. All terrible at…

It's frustrating that efficiency and being a good desktop citizen is such an afterthought for most browsers. Support for all the fancy web features imaginable is isn't worth much to me if means keeping my system pegged and destroying its battery life.

Re: 24-core CPU and I can’t move my mouse (2017)

#165
The trouble is no matter how much fast RAM, how much of a beast of your GPU is. How many threads your CPU has.

The UX is as hangy as the laggiest component.

That means if the Windows programmers decided that it needs to wait for every HDD to spin up to show you the contents of your start menu you're gonna have a bad time.

Re: 24-core CPU and I can’t move my mouse (2017)

#166

Earlier quoted context omitted.

The early 3rd century was an exciting time for computing. The big issue back then was Roman numerals were hard to convert to hex and binary.

Back then mainframes had specialized hardware to deal with them. Note: the other day I read ICL mainframes had specialized instructions to deal with pre-decimal pounds.

One of the IBM 1401 computers (1959) at the Computer History Museum has hardware support for pre-decimal pounds/shillings/pence, to perform arithmetic on these values and print them. Thus, the computer has three fundamental datatypes in hardware: arbitrary-length strings, arbitrary-length integers, and pounds/shillings/pence. Of course there were two competing standards for encoding pounds/shillings/pence, so the front panel has a knob to select the standard.

(Before decimalization, there were 12 pence in a shilling and 20 shillings in a pound. Mathematical operations on currency were both difficult and extremely common, so IBM provided hardware support as an option. There were boards of transistors so you could add, subtract, multiply, or divide currency values with a single operation, rather than an inconvenient sequence of instructions.)

Photos in my Twitter thread: https://twitter.com/kenshirriff/status/1364365985499602947

To get back to the original topic, I'll mention that my MacBook Air would drop keystrokes if I visited a website with, say, a video ad. I find it kind of appalling that computers in the 1960s could handle input from hundreds of keyboards at once, while a 2017 computer can't manage a single keyboard.

Re: 24-core CPU and I can’t move my mouse (2017)

#167
post #85

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Yeah, the 2019 MBPs were absolute abominations. I spent 5k AUD on a fully kitted out MBP and performance wise it’s one of the worst computers I’ve ever owned. I swore that would be the last Apple computer I ever bought, but then they released the M1s… and they are very good. Would recommend getting an M1 if at all possible. There’s still time to ask Santa for one.

I recommend getting a Framework. It's probably not as good as an M1, but it'll last you more than two years, and if it doesn't, you can just change the CPU for a better one without having to throw all the other, perfectly good hardware away.

Frameworks are nice in theory but they still have a long way to go when it comes to heat, fan noise, and battery life based on what I've seen owners of them say.

Re: 24-core CPU and I can’t move my mouse (2017)

#168
post #18

Earlier quoted context omitted.

In reality you never have a finely tuned load that uses all the resources all of the time. Processors spend a lot of time waiting for memory, so hyperthreading allows for better utilization of compute. It’s rare to have a workload that benefits from turning it off, and in those cases it’s usually because the hyperthread is hurting the cache hit rate enough to offset the gains.

I recently checked whether an ugly hack I implemented years ago for 30% performance gains ("halve the default OpenMP thread count at start of computation and restore it afterwards" -> effectively, disable hyperthreading) was still necessary. It's now apparently a 3x performance gain... All because I'm saturating memory bandwidth. I don't know whether to be happy or sad...

Ouch, looks like they’re clobbering each others cache. Also, well done. It looks like you optimized the hell out of your code.

Re: 24-core CPU and I can’t move my mouse (2017)

#169
post #11

If I recall, this is mainly caused by the shift to USB as the connector du jour. Since it's a poll centric protocol, under heavy load, system responsiveness decays. Back in the days of P/S 2, where input was interrupt driven, the background tasks would be interrupted by input coming in, ensuring the user could move the mouse around. Now whether they could get the outcome of a click to register is a different story. T…

On the MCU (device) side, you can command the poll in a data-received interrupt. Does it not work that way on the PC side? Ie, you never have to really block on the MCU.

It's the same for the host controller hardware, it exposes different interrupts which the host controller driver can make use of so you don't have to busy-wait. The details depend on the host controller interface the hardware provides though.

Re: 24-core CPU and I can’t move my mouse (2017)

#170

Ctrl-F in a 10MB PDF in Adobe DC lags when typing while (I guess) it builds the search suggestion index. On an i9 11th gen with over 20000 CPUmark, and 64 GB of RAM. Madness.

The only reason I would use Adobe over SumatraPDF is the need to open a PDF that use JavaScript, have 3D content inside, or has to be digitally signed.

Probably SumatraPDF is a lot faster because can't do all of those fancy things, but for reading a document and look for some keywords it's absolutely fantastic, and I don't need something better in 99% of the time.

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