Re:Everything old is new again: memory optimization
by dgb23 on Friday March 27, 2026 @07:11AM
(#47541240)
> all these numbers are way too small to make meaningful distinctions. Come back when you have a gigabyte.
I have to disagree. Bad performance is often a result of a death of a thousands cuts. This function might be one among countless similarly inefficient library calls, programs and so on.
Re:Everything old is new again: memory optimization
by rcxdude on Friday March 27, 2026 @09:29AM
(#47542425)
If you're not putting a representative amount of data through the test, you have no idea if the resource usage you're seeing scales with the amount of data or is just a fixed overhead if the runtime.
Re:Everything old is new again: memory optimization
by kloop on Friday March 27, 2026 @08:45AM
(#47542047)
> how big is the text file? I bet it's a megabyte, isn't it?
The edit in the article says ~1.5kb
Re:Everything old is new again: memory optimization
by pjc50 on Friday March 27, 2026 @09:10AM
(#47542250)
Single page on many systems, which makes using mmap() for it even funnier.
Re:Everything old is new again: memory optimization
by Filligree on Friday March 27, 2026 @09:57AM
(#47542725)
Not to mention inefficient in memory use. I would have expected a mention of interning; using string-views is fine, but making it a view of 4kB cache pages is not really.
Though I believe the “naive” streaming read could very well be superior here.
Re:Everything old is new again: memory optimization
by hrmtst93837 on Saturday March 28, 2026 @03:53AM
(#47552498)
"It only matters at scale" is how you end up with code that hoses mobile apps and embedded boards the moment somebody swaps in a file that is merely bigger than the toy input. These bugs start small. If the code slurps the whole input, staying under 1 GB is not proof of anything, it just means you have not hit the edge yet.
At this point I'd make two observations:
- how big is the text file? I bet it's a megabyte, isn't it? Because the "naive" way to do it is to read the whole thing into memory.
- all these numbers are way too small to make meaningful distinctions. Come back when you have a gigabyte. It gets more interesting when the file doesn't fit into RAM at all.
The state of the art here is : https://nee.lv/2021/02/28/How-I-cut-GTA-Online-loading-times... , wherein our hero finds the terrible combination of putting the whole file in a single string and then running strlen() on it for every character.