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GPT-4 API General Availability

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Re: GPT-4 API General Availability

#561

Earlier quoted context omitted.

Thank you for the update! Do you happen to know if there are quality comparisons somewhere, between llama.cpp and exllama? Also, in terms of VRAM consumption, are they equivalent?

Here's one: https://huggingface.co/spaces/mike-ravkine/can-ai-code-resul...

Thank you.

Re: GPT-4 API General Availability

#562
post #557

Earlier quoted context omitted.

Until recently, exllama was significantly faster, but they're about on par now (with llama.cpp pulling ahead on certain hardware or with certain compile-time optimizations now even). There are a couple big difference as I see it. llama.cpp uses `ggml` encoding for their models. There were a few weeks where they kept making breaking revisions which was annoying, but it seems to have stabilized and now also supports mo…

Thank you for the update! Do you happen to know if there are quality comparisons somewhere, between llama.cpp and exllama? Also, in terms of VRAM consumption, are they equivalent?

ExLlama still uses a bit less VRAM than anything else out there: https://github.com/turboderp/exllama#new-implementation - this is sometimes significant since from my personal experience it can support full context on a quantized llama-33b model on a 24GB GPU that can OOM w/ other inference engines.

oobabooga recently did a direct perplexity comparison against various engines/quants: https://oobabooga.github.io/blog/posts/perplexities/

On wikitext, for llama-13b, the perplexity of a q4_K_M GGML on llama.cpp was within 0.3% of the perplexity of a 4-bit 128g desc_act GPTQ on ExLlama, so basically interchangeable.

There are some new quantization formats being proposed like AWQ, SpQR, SqueezeLLM that perform slightly better, but none have been implemented in any real systems yet (the paper for SqueezeLLM is the latest, and has comparison vs AWQ and SpQR if you want to read about it: https://arxiv.org/pdf/2306.07629.pdf)

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