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nltoday at 5:50 AM8 repliesview on HN

> you find that the GPU often sits idle, not for lack of work, but because the CPU hasn't told it what to do next yet. This phenomenon is called a GPU bubble.

This is true, but I've never heard anyone refer to this as a GPU bubble before.

I think most people hear "GPU bubble" and think of a financial bubble of some kind.


Replies

SCdFtoday at 6:04 AM

It appears to be a real term? https://docs.vulkan.org/tutorial/latest/Synchronization/Asyn...

Very odd, but perhaps more familiar to graphics programmers? I will say I'd probably call it a stall, which is exactly what the Vulkan docs call it moments later, so :shrug:

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spaqintoday at 7:41 AM

Pretty sure that would be "[GPU performance] bottlenecked [by the CPU]" in most common terms.

_zoltan_today at 7:03 AM

while the title is misreading, when reading GPU profiling data, we do call these bubbles - where the GPU _could_ do something, but it's idle.

any time your GPU is idle = you are losing $$$ = your TCO is going up. you don't want that.

cmatoday at 6:02 AM

It's very common to call it a GPU bubble in gamedev, though not strictly for CPU induced bubbles.

vkazanovtoday at 6:16 AM

I saw it in literature on cpu pipelines in quotes, never without.

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nnevatietoday at 5:52 AM

Yes, the title seems off - I also thought I am going to be reading about the AI/pricing bubble.

Eisensteintoday at 10:38 AM

I thought it was normal for the AI field to confuse people by repurposing other terms of art? To: "transformer", "lora", "diffusion", "hallucination", etc, we can now add "bubble".

rusktoday at 5:54 AM

The term I would use would be “underutilised”

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