Depends on the available memory and size of the tables. I've worked on cases where time to compute didn't matter as much as shaving off three more bytes did. Large lookup tables would have absolutely killed us compared to running some math.

[–] henfredemars@infosec.pub 15 points 3 days ago (1 children)

Good point! Good point.

I've seen bubble sort implemented because we had data that said it was faster and was slightly smaller for the exact type data we were sorting and its expected distribution.

[–] disorderly@lemmy.world 22 points 3 days ago

I fondly remember the time I hired a QT expert onto an embedded app team and on his first project he imported a sort algorithm from std. He found the system got weird and glitchy, and often crashed.

Yeahhh turns out the algorithm he chose needed to make a copy in memory and the thread he was working in only had 2048 bytes of stack, so larger inputs would corrupt the stack allocated to the next thread. I had to explain to him that we had a full second to complete the math before we had to give back our semaphore, so saving a couple milliseconds on the sort was not a priority. Fun times.

[–] baines@lemmy.cafe 1 points 2 days ago (1 children)

not doubting you because the customer can be funny but wha?

if time to compute doesnt matter there are likely more minimal hardware options to optimize for look up tables and memory cost/space

[–] mushroommunk@lemmy.today 1 points 2 days ago (1 children)

There are so many situations where you can't just swap hardware. Robots on an assembly line? Yeah you've gotta use hardware that's gone through safety testing. They're not going to just swap hardware to make things easier. You want to ship an update, you do it in software and under strict testing regiment. Some of that hardware is 20 or 30 years old. Medical. Aeronautics. Aerospace. All of them and more are using older hardware that's often memory limited but can often just sit and process their next step, and they often don't have built in complex hardware features because those add potential failure points.

[–] baines@lemmy.cafe 1 points 2 days ago* (last edited 2 days ago) (1 children)

the hang up for me is more the not caring about time to compute

aeroish is my experience, and for me those have all cared about time to compute

generally that’s one of the biggest constraints to the point of being super strict

like major money being spent on modeled approximations and processing speed costs eclipsing pretty much everything on the design side

tables for weather, angles, altitude, position this would be tiny compared to some we’re using

30 year old equipment is even more taxed given the likely feature creep in my experience

[–] mushroommunk@lemmy.today 2 points 2 days ago

I'm guessing you were doing in flight aero stuff? I've been more in the medical and manufacturing space but the aero I did we were doing post-flight processing for reports. We had almost no memory to operate on, probably because of all the tables you're referencing that others were using.