Is llama.cpp meant to be slow at long context, even when you aren't using that context?

I am trying out a few fine-tunes of Qwen 3.5 9B @ IQ4_XS @ 131K context and trying to go mostly local (free beats cheap, after all). However, it is much slower than at, say 16K context, even when I am not actually using 131K tokens in the first place. Anyone know why this is? I am using the followin

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I am trying out a few fine-tunes of Qwen 3.5 9B @ IQ4_XS @ 131K context and trying to go mostly local (free beats cheap, after all). However, it is much slower than at, say 16K context, even when I am not actually using 131K tokens in the first place. Anyone know why this is? I am using the followin