Fix Plan

To resolve the issue, we need to modify the code to automatically disable v cache quantization when flash attention is not enabled. Here are the steps:

• Check if flash attention is enabled before attempting to use v cache quantization.
• If flash attention is not enabled, disable v cache quantization.

Example code changes:

if !flashAttnEnabled {
    // Disable v cache quantization
    vCacheQuantizationEnabled = false
    log.Println("V cache quantization disabled due to flash attention incompatibility")
}

Additionally, we need to ensure that the vCacheQuantizationEnabled flag is checked before attempting to create the llama context:

if vCacheQuantizationEnabled && !flashAttnEnabled {
    log.Fatal("V cache quantization requires flash attention, but it is not enabled")
}

We can also add a check to ignore v cache quantization if flash attention is not enabled:

if !flashAttnEnabled {
    // Ignore v cache quantization
    vCacheQuantizationType = ""
}

Verification

To verify that the fix worked, we can test the following scenarios:

• Set OLLAMA_FLASH_ATTENTION=1 and OLLAMA_KV_CACHE_TYPE=q8_0 and verify that v cache quantization is disabled when flash attention is not compatible with the model.
• Set OLLAMA_FLASH_ATTENTION=0 and OLLAMA_KV_CACHE_TYPE=q8_0 and verify that v cache quantization is disabled.

Extra Tips

• Make sure to update the documentation to reflect the changes to the v cache quantization behavior.
• Consider adding additional logging to help diagnose issues related to flash attention and v cache quantization.