Ok, so --ctx-size with a value != 0 means that we can override the default model context size. Since for obvious computation cost reasons we cannot use the 32k fresh context per each request, the trick you make is to use the 1k context (batch that includes local and semi-local code) that you enrich with the previous model responses by keeping them in and feeding them from KV cache? To increase the correlation between the current request and previous responses you do the shifting in KV cache?
Yes, exactly. You can set --ctx-size to a smaller value if you know that you will not hit the limit of 32k - this will save you VRAM.
To control how much global context to keep in the ring buffer (i.e. the context that is being reused to enrich the local context), you can adjust the "ring_n_chunks" and "rink_chunk_size". With the default settings, this amounts to about 8k tokens of context on our codebases when the ring buffer is full, which is a conservative setting. Increasing these numbers will make the context bigger, will improve the quality but will affect the performance.
There are a few other tricks to reduce the compute for the local context (i.e. the 1k batch of tokens), so that in practice, a smaller amount is processed. This further saves compute during the prefill.
Since qwen 2.5 turbo with 1M context size is advertised to be able to crunch ~30k LoC, I guess we can say then that the 32k qwen 2.5 model is capable of ~960 LoC and therefore 32k model with an upper bound of context set to 8k is capable of ~250 LoC?