---
name: llama-server-arch-verify
description: Verify llama.cpp binary supports a model architecture without relying on binary grep
---

# llama-server Arch Verification

## Problem
`grep -ac <arch> llama-server` returns 0 for ALL architecture names (including ones the binary is actively serving). The arch strings are stored in a packed/constructed form that grep can't catch.

## Solution
Verify arch support via the source registration table, not binary grep:

1. **Check the source registration** (`src/llama-arch.cpp` or `src/llmarch.h`):
   ```bash
   grep -n "gemma4\|qwen3_5\|<arch>" src/llama-arch.cpp
   ```
   If the arch is registered in the source at the commit the binary was built from, it's supported.

2. **Verify the binary is current**:
   ```bash
   stat -c "%y" /path/to/llama-server
   git log -1 --format=%cd <commit>
   ```
   The binary mtime should be after the commit date.

3. **Check for model-specific source files**:
   ```bash
   ls src/models/<arch>.cpp src/models/<arch>-*.cpp 2>/dev/null
   ```

4. **Check for spec-type support** (for MTP/draft models):
   ```bash
   /path/to/llama-server --help 2>&1 | grep "spec-type\|model-draft"
   ```

## KV Cache Types
The build's allowed `--cache-type-k` / `--cache-type-v` values:
`f32, f16, bf16, q8_0, q4_0, q4_1, iq4_nl, q5_0, q5_1`

**No true fp8 KV dtype** — `q8_0` is the "FP8 class" (1.0625 B/elem, 8.5 effective bits).

## Separate Draft Model (MTP assistant)
For models where the MTP head is a SEPARATE file (not in-file like Swift):
```bash
--spec-type draft-mtp \
--spec-draft-n-max 3 \
--spec-draft-model /path/to/mtp-assistant.gguf
```
The `--spec-draft-model` flag (aka `-md`, `--model-draft`) loads the separate draft file.