Add multi-latent attention, profiling instrumentation, other perf fixes#8
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andrewkchan merged 16 commits intomainfrom May 2, 2025
Merged
Add multi-latent attention, profiling instrumentation, other perf fixes#8andrewkchan merged 16 commits intomainfrom
andrewkchan merged 16 commits intomainfrom
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Adds a version of multi-latent attention and profiling instrumentation. Also adds a CLI option
-Lto "pin" (lock) model weights in memory, which is needed to fix an issue on my test machine (AWS r6a.12xlarge) where pages of the export tensors kept getting evicted by the OS, causing severe performance issues due to thrash.MLA requires the model to be re-exported with
python convert.py --mla .... The engine will automatically use MLA when running a model exported with the option.Currently, MLA is slower than MHA on short-context generations (~2.6 tok/s vs ~4 tok/s for 128-token generations with negligible prompt length on DeepSeek-V3 quantized to Q2K). The model active bytes when ignoring KV cache is slightly higher at 16.29 GB for MLA vs 14.99GB for MHA, so a regression is not unexpected, but one of this size is surprising and indicates the effective bandwidth is lower.
Model active bytes including KV cache (of context size 4096) is much better at 16.58GB for MLA vs 39.55GB for MHA. I haven't yet tested the token throughput difference.