fit: also take into account n_streams (#27496) fit: also take into account n_streams server: make the draft context follow the target context With a non-unified KV cache the target context now holds n_ctx_train tokens per sequence, while the draft context was still created with n_ctx = 0 and fell back to n_ctx_train / n_streams per sequence. A slot filled beyond that point makes the draft batch fail to decode, and the server answers 500 on the request. The draft context now takes its size from the target context, so both hold the same number of tokens per sequence. Contexts that share their cells with the target no longer need the kv_size override.

The memory reserved for the draft model before fitting is measured at the largest context the target can take, since the draft context grows with the target and a fixed byte margin cannot express that. fit: take an optional second model into account Illustrates the alternative discussed on the draft context fix. The memory of a draft or MTP context is currently handed to the fit as a fixed byte margin, which cannot express a memory that grows with the context the fit is still deciding on. common_fit_params now takes an optional second…