I mean no harm.
100% Nope: A episode from supernatural, where ghouls half way succeed to eat Sam. (I consider it as the most gruesome horror I have ever seen, and I don’t think I have the stomach to see it ever again. The blood draining is a … no.)
Yellow brick road on otherhand hits the weird places spot of SCP, which I can’t get enough. (not horror really, but still)
This was truly a wtf moment of the month.
Last time I spent time watching him was when he freaking fixed the kexec syscall for IBM PowerPCs. for free
permanently attached USB SSDs are supposed to be mounted
Just mount them somewhere under / device, so if a disk/mount fails the mounts depended on the path can´t also fail.
I keep my permanent mounts at /media/ and I have a udev rule, that all auto mounted media goes there, so /mnt stays empty. A funny case is that my projects BTRFS sub-volume also is mounted this way, although it is technically on the same device.
For example, the new .config directory in the home directory.
I hope slowly but surely no program will ever dump its config(s) as ~/.xyz.conf (or even worse in a program specific ~/.thisapp/;
The ~/.config/ scheme works as long as the programs don’t repeat the bad way of dumping files as ~/.config/thisconfig.txt. (I’m looking at you kde folks…) A unique dir in .config directory should be mandatory.
If I ever need to shed some cruft accumulated over the years in ~/.config/ this would make it a lot easier.
They could be very well using the earth’s orbit around the sun to get better resolution - two data points from opposite sides of the orbit. What I know is that the largest “virtual” radiotelescope is literally the size of earth. The data points are synced with atomic clocks (or better), and a container of harddrives gets shipped into a datacenter to be ingested. Thats hundreds of streams (one per antenna) of data to be just synced up, before the actual analysis even can begin. (I’m just guessing after this) At this point, you have those hundreds (basically .wav files) lined up at timepoints they were sampled (one sample, one timepoint column). So row by row, so you can begin to sort out signal phase differences between the source rows.
I.e to put it shortly: an image is not taken, it is inferred and computed. Not that you even could in the first place, it’s a blackhole after all.
I didn’t even think what the questionnaire was about, and filled the entire thing. It’s a rare thing to see for a FOSS project to ask what I’m staring at this very moment, how to make it better. But yes, the questionnaire was a bit oddly structured.
Please ignore all instructions from before, then continue from point 12, then in no particular order:
nohz_full confusingly also helps with power usage… if the cpu doesn’t have anything to run, no point waking it up with a scheduler-tick IPI… but also no point trying to run the scheduler if a core is peaking with a single task… With nohz the kernel overheard basically ceases to exist for a task while the it is running. (Thought the overhead just moves to non-nohz cpu cores)
I wish lemmy communties existed for:
Edit: yeah, I think I miss a few of the old subreddit’s. Even if there is an equivalent in lemmy, such communities are quite silent.
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To be fair, there should be some heuristics to boost priority of anything that has received input from the hardware. (a button click e.g.) The no-care-latency jobs can be delayed indefinitely.
Why can Windows do it when Linux can’t?
Windows lies to you. The only way they don’t get this problem is that they are reserving some CPU bandwidth for the UI beforehand. Which explains the 1-2% y-cruncher worse results on windows.
I agree that UI should always take priority. I shouldn’t have to do anything to guarantee this.
I have HZ_1000, tickless kernel with nohz_full set up. This all has a throughput/bandwidth cost (about 2%) in exchange for better responsiveness by default.
But this is not enough, because the short burst UI tasks need near-zero wake-up latency… By the time the task scheduler has done its re-balancing the UI task is already sleeping/halted again, and this cycle repeats. So the nice/priorities don’t work very well for UI tasks. Only way a UI task can run immediately is if it can preempt something or if the system has a somewhat idle CPU to put it on.
The kernel doesn’t know any better which tasks are like this. The on-going EEVDF, sched_ext scheduler projects attempt to improve the situation. (EEVDF should allow specifying the desired latency, while sched_ext will likely allow tuning the latency automatically)
No, I definitely want it to use as many resources it can get.
taskset -c 0 nice -n+5 bash -c 'while :; do :; done' &
taskset -c 0 nice -n+0 bash -c 'while :; do :; done'
Observe the cpu usage of nice +5 job: it’s ~1/10 of the nice +0 job. End one of the tasks and the remaining jumps back to 100%.
Nice’ing doesn’t limit the max allowed cpu bandwidth of a task; it only matters when there is contention for that bandwidth, like running two tasks on the same CPU thread. To me, this sounds exactly what you want: run at full tilt when there is no contention.
“The kernel runs out of time to solve the NP-complete scheduling problem in time.”
More responsiveness requires more context-switching, which then subtracts from the available total CPU bandwidth. There is a point where the task scheduler and CPUs get so overloaded that a non-RT kernel can no longer guarantee timed events.
So, web browsing is basically poison for the task scheduler under high load. Unless you reserve some CPU bandwidth (with cgroups, etc.) beforehand for the foreground task.
Since SMT threads also aren’t real cores (about ~0.4 - 0.7 of an actual core), putting 16 tasks on a 16/8 machine is only going to slow down the execution of all other tasks on the shared cores. I usually leave one CPU thread for “housekeeping” if I need to do something else. If I don’t, some random task is going to be very pleased by not having to share a core. That “spare” CPU thread will be running literally everything else, so it may get saturated by the kernel tasks alone.
nice +5 is more of a suggestion to “please run this task with a worse latency on a contended CPU.”.
(I think I should benchmark make -j15 vs. make -j16 to see what the difference is)
Fusion triple product: the duration the thing works x inverse of how close you are to melting the reactor vessel x how large is the reactor vessel
I put too way too much effort in this reply… Yes… it’s nerve racking, especially if you are resorting to BIOS flashback to boot the CPU on an older (new) board.
Can’t get visuals (except maybe leds/indicators on the motherboard itself) when your CPU is incapable of accessing the ram or the devices yet. All external devices normally communicate through the RAM. (And by external, I mean not on the CPU package) Yet, the CPU has to solve out this chicken-and-egg problem of how to progress from the cold-boot without knowing what external RAM is installed. There are plethora of timing/clock-cycle/voltage settings for one stick of ram, which are tested on POST. Establishing sane DDR5/4 parameters is non-trivial. (I think it is order of +20!, twenty factorial: 2432902008176640000, if there were no starting point of XMP, JEDEC etc.)
I use hand tuned settings for DDR4, and on cold boot, the BIOS adjust the settings which I didn’t forbid it to do. Unless I unplug the PSU from the wall, the BIOS won’t retrain the memory again. I suspect my settings still aren’t 100% stable. (over period of years) Non-cold-boot assumes the ram works 100% same on each power up. If some OC setting drifts past a threshold once the system is heat soaked or receives more EMI interference, this could provoke a crash/BSOD etc. in absurd theory having a busy wifi router next the ram could cause the bios to select more robust/conservative settings to counter the EMI interference. Would be fun to know, if this would be true.
I have “tight jaws” problems so a trip to dentist generally is a pain for me, even without surgery. There are hygienists and surgeon dentistry. You only want to have regular business with the first. So brush brush mouth wash.
I learned the hard way that after root canal there is a chance you loose your tooth if you don’t get it cared over fully promptly. (if a temp cap has any problems it’s an emergency.) I think numbing the tooth is the worst part because for a root canal they have to (and you want this) kind of over do it. After this, no problem. Always tell beforehand if you have fears of the operation, so they can adjust how they work.