frank-default-small: use q8_0 (not q8_KV) KV cache on ik_llama

The ik_llama fast q8_KV cache type crashes at model init on this
QWEN3MOE/MTP + multimodal arch at commit b166e269 with a ggml_view size
assert (ggml.c:5427) right after the output buffer is created, looping
the service. Empirically isolated by toggling cache type: q8_0 and f16
load and serve (smoke-tested correct output), q8_KV asserts. Switch to
q8_0 + Hadamard (K/V), which still gives the 8-bit cache + Hadamard
quality win. KB updated with the crash lesson.
This commit is contained in:
Frank
2026-08-26 03:23:18 -07:00
parent e2085f1f7d
commit 0e5c37f2f8
5 changed files with 32 additions and 17 deletions
+14 -4
View File
@@ -1,7 +1,7 @@
---
type: reference
title: ik_llama.cpp on Dankserver (Ornith Q6_K)
description: ikawrakow/ik_llama.cpp replaces upstream llama.cpp for frank-default-small on the RTX 3090. q8_KV KV cache with Hadamard, split-mode none (graph requires >=2 GPUs), ngram-mod canonical args, and explicit CPU-expert offload. Includes the mandatory CUDA/IQK FA_ALL_QUANTS build flags.
description: ikawrakow/ik_llama.cpp replaces upstream llama.cpp for frank-default-small on the RTX 3090. q8_0 KV cache with Hadamard (the fast q8_KV type crashes on this arch at this commit), split-mode none (graph requires >=2 GPUs), ngram-mod canonical args, and explicit CPU-expert offload. Includes the mandatory CUDA/IQK FA_ALL_QUANTS build flags.
tags:
- ikllama
- llamacpp
@@ -104,14 +104,24 @@ Files: `scripts/serve-frank-small.sh`, `scripts/frank-default-small.env`,
`scripts/frank-default-small.service` in the repo. The service just calls
the serve script; the env file holds all tunables.
### KV cache: q8_KV + Hadamard
### KV cache: q8_0 + Hadamard
- `CACHE_TYPE_K=q8_KV`, `CACHE_TYPE_V=q8_KV` — fast quant type (ik
PR 208). Passes `--cache-type-k q8_KV --cache-type-v q8_KV`.
- `CACHE_TYPE_K=q8_0`, `CACHE_TYPE_V=q8_0` — standard 8-bit KV cache type
(passes `--cache-type-k q8_0 --cache-type-v q8_0`).
- `K_CACHE_HADAMARD=1`, `V_CACHE_HADAMARD=1` — `--k-cache-hadamard` and
`--v-cache-hadamard`. The Hadamard transform preserves KV quality at
8-bit (docs recommend it for quantized KV below Q6_0). Implemented for
both the CUDA (`ggml-cuda/hadamard.cu`) and CPU (IQK) paths.
- Flash-attention is **on by default** (no `-fa` flag needed).
> ⚠️ **Do not use `q8_KV` (fast type) here.** On this commit (`b166e269`)
> the fast `q8_KV` cache type crashes at model init on this QWEN3MOE/MTP +
> multimodal arch with a `ggml view` size assertion
> (`ggml.c:5427: GGML_ASSERT(view_src == NULL || ... data_size + view_offs`)
> right after the output buffer is created. It loops the service. Plain
> `q8_0` (and `f16`) work and were smoke-tested with correct output; this
> config uses `q8_0`. This was isolated empirically by toggling cache type
> while keeping the override/hadamard flags.
These keep the 163840-slot / 491520-pool context while roughly halving KV
cache RAM vs f16.
+2 -2
View File
@@ -20,7 +20,7 @@ graph LR
B2[ik_llama.cpp build b166e269
frank-default-small, port 7770]
C[Ornith-1.5-35B-A3B-CRACK Q6_K
ngram-mod, q8_KV + Hadamard cache, 491520 ctx]
ngram-mod, q8_0 + Hadamard cache, 491520 ctx]
A --> B2 --> C
end
@@ -57,7 +57,7 @@ MTP draft + Turbo4 V cache, 262K ctx / 1 slot]
- [[dealign-ornith-crack]] — the dealign Ornith-1.5-35B-A3B CRACK model on
Dankserver (frank-default-small, active 2026-08-24)
- [[ikllama-ornith-dankserver]] — the ik_llama.cpp runtime for
frank-default-small (2026-08-26): q8_KV + Hadamard KV cache,
frank-default-small (2026-08-26): q8_0 + Hadamard KV cache,
split-mode none (single-GPU), mandatory FA_ALL_QUANTS build flags
- [[kingjones-strix-mtp]] — the active kingjones Qwen3.8-27B ROCmFP4 STRIX MTP
model on Dankclaw (restored 2026-09-01 after the Q8_0 AGENT experiment)
+1 -1
View File
@@ -110,7 +110,7 @@ The LLM inference fleet on the two hosts. Full index:
- [[ciru-activefpx-promptforge]] — the RETIRED v3 CIRU PromptForge runtime on Dankclaw (superseded 2026-08-24)
- [[kingjones-strix-mtp]] — the kingjones Qwen3.8-27B ROCmFP4 STRIX MTP model on Dankclaw (active)
- [[dealign-ornith-crack]] — the dealign Ornith-1.5-35B-A3B CRACK model on Dankserver (active)
- [[ikllama-ornith-dankserver]] — the ik_llama.cpp runtime for frank-default-small (q8_KV + Hadamard KV cache, split-mode none; 2026-08-26)
- [[ikllama-ornith-dankserver]] — the ik_llama.cpp runtime for frank-default-small (q8_0 + Hadamard KV cache, split-mode none; 2026-08-26)
- [[kairic-edge]] — the retired Kairic Edge IU4 experiment (2026-08-22)
- [[dflash2-large-vulkan]] — the retired DFlash2 Vulkan deployment (2026-08-21)
- [[Dankserver System Specs]] — the RTX 3090 box hardware
+11 -9
View File
@@ -5,12 +5,12 @@
# 2026-08-26 from commit b166e269) on RTX 3090 24 GB; Ryzen 7 7700X; 62 GB
# RAM. Previous runtime was upstream llama.cpp b10121. MoE expert weights
# pinned to CPU with an explicit --override-tensor regex (not --n-cpu-moe).
# KV cache quantized to q8_KV with Hadamard transforms on both K and V.
# --split-mode graph enabled (single GPU; retained per operator preference).
# KV cache quantized to q8_0 with Hadamard transforms on both K and V.
# Split mode none (single GPU; graph would require 2+ devices).
#
# Build flags (IK_FA note, see docs/LLM/ikllama-ornith-dankserver.md) must
# ALWAYS include: -DGGML_CUDA_FA_ALL_QUANTS=ON and -DGGML_IQK_FA_ALL_QUANTS=ON
# so the q8_KV + Hadamard KV cache combos compile into the CUDA/CPU FA
# so the quantized + Hadamard KV cache combos compile into the CUDA/CPU FA
# kernels. Replacing the HauhauCS Qwen3.6-35B-A3B model on 2026-08-24.
# Switched from CRACK Q8_0 to Q6_K on 2026-08-25.
#
@@ -67,12 +67,14 @@ OVERRIDE_BUFT=CPU
# OVERRIDE_EXPERT below.
N_GPU_LAYERS=999
# KV cache on GPU, both K and V at q8_KV (fast quant type on ik_llama, PR 208)
# plus Hadamard transforms on both caches to preserve quality at 8-bit.
# For quantized KV below Q6_0 the docs recommend --k-cache-hadamard; we apply
# --v-cache-hadamard to V as well.
CACHE_TYPE_K=q8_KV
CACHE_TYPE_V=q8_KV
# KV cache on GPU, both K and V at q8_0 plus Hadamard transforms on both
# caches to preserve quality at 8-bit. NOTE: ik_llama's fast q8_KV type
# crashes at model init on this MTP/multimodal arch with a ggml_view size
# assert (ggml.c:5427) at commit b166e269; plain q8_0 works. Docs recommend
# --k-cache-hadamard for quantized KV below Q6_0; we apply --v-cache-hadamard
# to V as well. Flash-attention is on by default.
CACHE_TYPE_K=q8_0
CACHE_TYPE_V=q8_0
K_CACHE_HADAMARD=1
V_CACHE_HADAMARD=1
+4 -1
View File
@@ -7,11 +7,14 @@
# 35B-total / 3B-active MoE-dense hybrid with an MTP head bundled in the GGUF;
# this service uses ngram-mod instead of MTP speculation.
#
# KV cache: q8_KV with Hadamard transforms on K and V (requires a build with
# KV cache: q8_0 with Hadamard transforms on K and V (requires a build with
# GGML_CUDA_FA_ALL_QUANTS=ON + GGML_IQK_FA_ALL_QUANTS=ON; see the env file).
# The ik_llama fast q8_KV type crashes at init on this arch (ggml.c:5427);
# q8_0 is used instead.
#
# Split mode is none: Dankserver has a single RTX 3090 and ik_llama rejects
# split-mode graph with fewer than 2 devices (hard load error).
#
# Expert offload: the expert (FFN exps) tensors selected by the layer-bounded
# --override-tensor pattern are pinned to CPU. Selected full-attention and