Comment by hvenev
1 day ago
In `libnvidia-nvvm.so` the string `cutlass` appears right after `Memory Dependence Analysis` and `memdep`. Perhaps it acts as an optimization attribute of some sort, where the compiler is allowed to make assumptions about the kernel's behavior that are not valid in general?
yes, that is a very usual way (known practices) of vendors applying specific optimizations for known things.
It is also part of the benchmarks game they play against each other.
The link is long dead and the Wayback machine doesn’t have a copy.
But in 2001 ATI was caught applying optimizations to Quake 3 when someone realized if you renamed the executable from “quake” to “quack” the score dropped a ton. It was a big scandal.
I know that’s common now but that wasn’t a thing that was done at the time.
Was it a scandal at the time? My understanding of how per-game card-driver optimizations work today is:
1. AAAA Game Studio shits out another unoptimized clunker
2. nvidia considers it a reputational risk if games run at 30 FPS on a 5090
3. They go in, look at the perverse ways the game misuses rendering primitives, and then hacks shit in to make whatever bad things they're doing less bad.
As a gamer, this seems fine to me and i generally blame the AAAA devs for being bad at their jobs or AAAA studio leads for being ok shipping unoptimized messes.
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In at least one past version of Windows (circa 1990s), if you tried to replace the default web browser of IE with another choice you were given an Open File dialog window to choose the executable.
Funny quirk, though: that particular window wouldn't show files named firefox.exe. It would accept that as typed input, if you were at the correct folder, but the file listing omitted that particular file.
Maybe it was mozilla.exe; it was a long time ago. But that was the discovery that pushed me off IE forever.
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There are bugs that certain games rely on and features that some don’t use. I’m currently trying to optimize a library out of spite. (I want it to work better than the competitor that caused me a lot of problems on a recent project). The amount of conditional logic around what is essentially a function to increment a value is breathtaking.
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the etiology of this hack is pretty obvious with a simple google search:
https://docs.nvidia.com/cutlass/index.html
it presumably makes various assumptions and speedups for NVIDIA's matrix multiplication library... called cutlass
It’s really strange for established companies to waste their credibility on games like that…
Never underestimate how much human ego will control actions.
I was pretty young at the time, but I recall the market for graphics being a lot wider open at the time Quake was released. Remember 3dfx? They produced the Voodoo series of graphics cards. They're barely a distant memory now.
Quake was also the standard for a game that was willing to fully exploit the hardware of the time.
Thats very likely imo