Files
tinygrad/test/unit/test_llm_server.py
George HotzandGitHub 7e561fcb97 mergable fast RDNA3 Qwen 3.8 (#17512)
* mergable fast RDNA3 Qwen 3.6

* AMD

* quant 256 multiple

* cleanup cast

* llm kernels: adapt to Ops.BIND removal

Variables are 0-d ALU BUFFERs in the tensor graph and take the ALU PARAM form
inside kernels (UOp.variable(param=True)). Add kernel_var helper for the
conversion, and keep start_pos in bound form at the graph level so function
implicit-input collection and the schedule's binds rename-back line up.

* adaptive prefill chunk sizes for recurrent models + iq4xs model entry

one TinyJit per static prefill chunk size: capture 128 and 32 at warmup,
generate picks the largest that fits the remaining prompt. long prompts
prefill 2x faster (555 tok/s on Qwen3.6-27B IQ4_XS) without pushing short
prompts through token-by-token decode.

* minimize diff: early-return custom attention path, keep master state init

* minimize: master _attention with gated fused-scan swap, kernels/amd only, single chunk size

- GatedDeltaNetBlock._attention keeps master's symbolic-padding structure;
  the recurrent scan is swapped for the fused gated_delta_prefill kernel only
  on RDNA3 with static shapes (fast_scan), everything else uses the old path
- all AMD kernel code lives in tinygrad/llm/kernels/amd.py (drop kernels/__init__.py,
  drop the generic fallback kernel - the old scan covers non-RDNA3)
- single prefill chunk size 32; non-RDNA3 recurrent keeps master's chunk_size=1
- the conv+normalize miscompile doesn't trigger with master's window-buffer conv,
  so the contiguous workaround is dropped

* warmup: single code path for fast and old recurrent

* drop fast_scan/fast_recurrent flags, inline the RDNA3 gate (cached)

* generate: chunk size is always 32, no device gating

static chunks for recurrent models everywhere: the fused kernel path on RDNA3,
the old scan elsewhere (which is also faster chunked than token-by-token)

* warmup: drop redundant _init_state loop (lazy init in the eager step covers it)

* symbolic-length prefill with the custom kernels

the prefill path is fully symbolic again (master's generate, one prefill graph
for every chunk size, no static-tail decode): padded steps are exact no-ops in
the scan (beta=0, alpha=exp(0)=1), flash attention positions queries at
start_pos instead of valid_kv_len-M, and quant linears pad to the chunk bucket

prefill 401 tok: 284 -> 348 tok/s on Qwen3.8-27B IQ4_XS (tail chunks no longer
decode token-by-token), decode unchanged at 45 tok/s

* cli: default qwen3.6:27b to the fast IQ4_XS quant, add qwen3.8:27b

Q4_K_M falls back to slow inline dequant with the custom kernels, IQ4_XS is
the fast path. qwen3.8 quants use unsloth's UD (dynamic) naming

* warmup: back to master's two-liner plus a cache reset

with symbolic prefill, generate([0])'s 1-token chunk captures the symbolic
prefill graph that serves every chunk size, and JIT batching on capture
measurably doesn't matter with the fused kernels (347.7 tok/s either way)

* cli: pin qwen3.8:27b to the pre-UD revision

the UD-IQ4_XS replacement mixes in Q3_K tensors (ggml type 11) the loader
doesn't support; the pinned revision is byte-identical to the known-good file

* warmup: identical to master

the leftover cache is self-consistent: get_start_pos only reuses a full
strict-prefix match, everything else restarts with a state reset

* model: hoist the quantized_attention import to the top level

* hoist the GDN query scale out of the branch, restore master dtype.py

the scale is the same op in both paths, apply it once after the transpose.
the dtype.py diff was a stale pre-SPEC=2 copy, not intentional work

* gated_delta_prefill: don't pass the bound start_pos as a call src

device-less param buffers in call srcs crash hcq2's _get_enqueue_devs. the
var already reaches the graph through the state AFTER chain (conv state
store), same as the flash kernels' valid_end

* llm: half KV cache with custom flash kernels, drop the int8 quantized cache

matches master's new half cache default: no scales, no packing, one less
buffer. the store casts to half explicitly (buffer-only half usage misses
the renderer's half define). 45.5 tok/s decode, 348.7 tok/s prefill —
same as int8

* llm: zero-init the KV cache

the int8 path was accidentally protected from uninitialized memory by its
zero-initialized scale buffer; with a plain half cache the flash prefill
kernel's P*V wmma computes 0*NaN=NaN on masked lanes past the valid region
(manifested as garbage tokens at 32k context where the allocator reuses
dirty VRAM)

* gate that

* llm/kernels/amd: reorganize by kernel family, drop the clutter

sections: shared helpers, quant linear, flash attention, gated delta prefill.
no AxisType.WEAK (default), no ALLOW_DEVICE_USAGE override (unneeded), magic
numbers become names (QUANT_SIZES, Q5_K/Q6_K/IQ4_XS), merged wrapper layers
(flash_attention_causal_cached folded into flash_attention), one _unbind
helper for the bound-var dance

* test: universal recurrent reuse assertion, fix lambda lint

* 1-token chunks have a static shape: they are decode steps

a 1-token chunk routes to the decode graph via the existing dispatch, so
warmup and decode-only workloads never build the big symbolic prefill graph:
CI benchmark command 12m50s -> 5m29s (master: 6m48s), 220 -> 123 compile jobs

also restores the ALLOW_DEVICE_USAGE override in amd_custom_kernels_supported:
Device[] asserts inside @function contexts (ALLOW_DEVICE_USAGE=0), and the
first gate call can happen there depending on test order

* generate: back to plain symbolic binding, the static-1 rule wasn't worth it

* custom kernels: Q4_K support (ggml type 12)

Q4_K is Q5_K without the high-bit array: same d/dmin/scales layout (so
_q5_scales works unchanged), 144-byte blocks, qs at word 4. both the dp4a
decode kernel and the WMMA prefill kernel take a ggml_type branch now.

Qwen3-8B Q4_K_M: decode 16.5 -> 114.8 tok/s, prefill 69 -> 536 tok/s

* raise line count to 26500 (qwen did it)

* benchmark qwen3.8

* little updates
2026-08-23 22:46:35 -07:00

237 lines
9.8 KiB
Python

import unittest
import numpy as np
from unittest.mock import patch
from tinygrad import Tensor, UOp
from tinygrad.nn.state import get_state_dict
from tinygrad.schedule import schedule_cache
from tinygrad.llm.model import Transformer, TransformerConfig
from tinygrad.llm.serve import StreamRouter
TEST_CONFIG = TransformerConfig(num_blocks=1, dim=64, hidden_dim=128, n_heads=2, n_kv_heads=2,
norm_eps=1e-5, vocab_size=100, head_dim=32, rope_theta=10000.0, rope_dim=32, v_head_dim=32, max_context=32)
V_START_POS = UOp.variable("start_pos", 0, TEST_CONFIG.max_context-1)
V_TOKS = UOp.variable("toks", 1, 32) # 32 is the default chunk_size in generate
class TestTransformerGenerate(unittest.TestCase):
def test_warmup(self):
model, calls = Transformer(TEST_CONFIG), []
def generate(tokens, **kwargs):
calls.append(tokens)
yield from (1, 2)
with patch.object(model, "generate", generate): model.warmup()
self.assertEqual(calls, [[0], [0]])
def test_warmup_then_generate_with_default_chunk(self):
# warmup must not capture JIT graphs that generate()'s default chunk_size then rejects
model = Transformer(TEST_CONFIG)
model.warmup()
self.assertIsInstance(next(model.generate([5, 6, 7, 8])), int)
def test_first_recurrent_generate_before_state_init(self):
model = Transformer(TEST_CONFIG)
model.has_recurrent_block = True
with patch.object(Transformer, '__call__', return_value=Tensor([[42]])):
self.assertEqual(next(model.generate([0])), 42)
def test_recurrent_live_state_reuse(self):
model = Transformer(TEST_CONFIG)
model.has_recurrent_block = True
model._cached_tokens = [1, 2, 3, 4, 5]
self.assertEqual(model.get_start_pos([1, 2, 3, 4, 5, 42, 10]), 5)
calls = []
def mock_call(self, tokens, start_pos, temperature, **kwargs):
calls.append((tokens.shape, start_pos))
return Tensor([[42]])
with patch.object(Transformer, '__call__', mock_call):
next(model.generate([1, 2, 3, 4, 5, 42, 10]))
# resumes from the reused state at position 5 and consumes the 2 new tokens (one chunk or two decode steps)
self.assertEqual(calls[0][1], V_START_POS.bind(5))
def ntok(shape): return shape[1] if isinstance(shape[1], int) else shape[1].unbind()[1]
self.assertEqual(sum(ntok(c[0]) for c in calls), 2)
def test_recurrent_divergent_prompt_restarts(self):
model, calls = Transformer(TEST_CONFIG), []
model.has_recurrent_block, model._cached_tokens = True, [1, 2, 9]
def mock_call(self, tokens, start_pos, temperature):
calls.append(start_pos)
return Tensor([[42]])
with patch.object(Transformer, '__call__', mock_call): next(model.generate([1, 2, 10, 11]))
self.assertEqual(calls[0], V_START_POS.bind(0))
def test_template_starts_reasoning(self):
router = StreamRouter(reasoning=True)
self.assertEqual(list(router.route("reasoning</think>answer")),
[("reasoning_content", "reasoning"), ("content", "answer")])
def test_kv_cache_reuse(self):
"""Test that generate reuses the KV cache when tokens extend the cached prefix."""
model = Transformer(TEST_CONFIG)
captured_inputs = []
def mock_call(self, tokens, start_pos, temperature, **kwargs):
captured_inputs.append((tokens.shape, start_pos))
return Tensor([[42]])
with patch.object(Transformer, '__call__', mock_call):
# first conversation: prefill 5 tokens + 1 decode
tokens = [1, 2, 3, 4, 5]
gen = model.generate(tokens)
next(gen) # prefill
next(gen) # decode
# second call extends the conversation — cached prefix should be reused
captured_inputs.clear()
tokens = [1, 2, 3, 4, 5, 42, 42, 10, 11, 12]
gen = model.generate(tokens)
next(gen)
# should process tokens[6:] = [42, 10, 11, 12] since first 6 have cached k/v
self.assertEqual(captured_inputs, [((1, V_TOKS.bind(4)), V_START_POS.bind(6))])
def test_kv_cache_invalidation(self):
"""Test that generate invalidates the KV cache when tokens diverge from the cached prefix."""
model = Transformer(TEST_CONFIG)
captured_inputs = []
def mock_call(self, tokens, start_pos, temperature, **kwargs):
captured_inputs.append((tokens.shape, start_pos))
return Tensor([[42]])
with patch.object(Transformer, '__call__', mock_call):
# first conversation
gen = model.generate([1, 2, 3, 4, 5])
next(gen)
# completely different prompt — KV cache should be invalidated
captured_inputs.clear()
gen = model.generate([10, 20, 30])
next(gen)
# should process all 3 tokens from start
self.assertEqual(captured_inputs, [((1, V_TOKS.bind(3)), V_START_POS.bind(0))])
def test_two_prompts_schedule_cache(self):
"""Third prompt should hit the schedule cache, not miss (first two warm up both jits: prefill + decode)."""
from dataclasses import replace
model = Transformer(replace(TEST_CONFIG, max_context=64))
# first two prompts warm up both jits (prefill + decode)
ids = list(range(1, 6))
gen = model.generate(ids)
for _ in range(3): next(gen)
ids += list(range(10, 15))
gen = model.generate(ids)
for _ in range(3): next(gen)
cache_size_after_warmup = len(schedule_cache)
# third prompt should reuse the same schedule cache entries, not create new ones
ids += list(range(20, 25))
gen = model.generate(ids)
for _ in range(3): next(gen)
self.assertEqual(cache_size_after_warmup, len(schedule_cache),
f"third prompt added {len(schedule_cache) - cache_size_after_warmup} new schedule cache entries (expected 0)")
def test_chunked_prefill(self):
"""When prompt > chunk_size, all chunks should be prefill"""
from tinygrad.uop.ops import resolve
from dataclasses import replace
model = Transformer(replace(TEST_CONFIG, max_context=64))
def get_prefill_flags(tokens, chunk_size):
is_prefill = []
def mock_call(self, tokens, start_pos, temperature, **kwargs):
is_prefill.append(resolve(tokens.shape[1] != 1))
return Tensor([[42]])
with patch.object(Transformer, '__call__', mock_call):
gen = model.generate(tokens, chunk_size=chunk_size)
for _ in range(3): next(gen)
model._cached_tokens = []
return is_prefill
# 8 tokens, chunk_size=4 -> 2 prefill chunks
self.assertEqual(get_prefill_flags(list(range(8)), 4), [True, True, False, False])
# 9 tokens, chunk_size=4 -> 3 prefill chunks (4+4+1)
self.assertEqual(get_prefill_flags(list(range(9)), 4), [True, True, True, False, False])
# 4 tokens, chunk_size=4 -> 1 prefill chunk
self.assertEqual(get_prefill_flags(list(range(4)), 4), [True, False, False])
def test_chunked_prefill_kv_cache_matches_single_chunk(self):
config = TransformerConfig(num_blocks=1, dim=8, hidden_dim=16, n_heads=1, n_kv_heads=1, norm_eps=1e-5,
vocab_size=32, head_dim=4, rope_theta=1000000, rope_dim=4, qk_norm=4, v_head_dim=4, max_context=16)
def model():
m = Transformer(config)
rng = np.random.RandomState(1234)
for t in get_state_dict(m).values():
t.assign(Tensor(rng.uniform(-1, 1, t.shape).astype(np.float32))).realize()
return m
def prefill(m, chunk_size):
gen = m.generate(list(range(1, 9)), chunk_size=chunk_size, temperature=0.0)
next(gen)
return [b.cache_kv.numpy() for b in m.blk]
for g, r in zip(prefill(model(), 4), prefill(model(), 8)):
np.testing.assert_allclose(g[:, :, :, :8, :], r[:, :, :, :8, :], atol=1e-5)
def test_kv_cache_resume_matches_fresh(self):
model = Transformer(TEST_CONFIG)
# generate 2 tokens, then abandon
prompt = list(range(1, 6))
gen = model.generate(list(prompt))
out1, out2 = next(gen), next(gen)
# resume with conversation history + new user tokens appended
extended = prompt + [out1, out2, 10, 11, 12]
gen = model.generate(list(extended))
resumed_out = [next(gen) for _ in range(3)]
# compare against fresh generation (no cache) of the same prompt
model._cached_tokens = []
gen = model.generate(list(extended))
fresh_out = [next(gen) for _ in range(3)]
self.assertEqual(fresh_out, resumed_out)
def test_temperature_zero_is_greedy(self):
"""Temperature 0 (or near 0) should produce deterministic output."""
model = Transformer(TEST_CONFIG)
tokens = list(range(1, 6))
results = [list(zip(range(5), model.generate(list(tokens)))) for _ in range(3)]
# all runs should produce the same tokens
self.assertEqual(results[0], results[1])
self.assertEqual(results[1], results[2])
def test_temperature_high_produces_variety(self):
"""High temperature should produce different outputs across runs."""
model = Transformer(TEST_CONFIG)
tokens = list(range(1, 6))
runs = set()
for _ in range(5):
gen = model.generate(list(tokens), temperature=2.0)
out = tuple(next(gen) for _ in range(10))
runs.add(out)
# with temperature=2.0, we should see at least 2 distinct outputs across 5 runs
self.assertGreater(len(runs), 1, "high temperature should produce varied outputs")
def test_recurrent_temperature_high_produces_variety(self):
model = Transformer(TEST_CONFIG)
model.has_recurrent_block = True
outputs = {model.forward(Tensor([[1]]), 0, Tensor([2.0])).item() for _ in range(5)}
self.assertGreater(len(outputs), 1)
def test_temperature_passed_to_forward(self):
"""Temperature from generate should be passed through to __call__."""
model = Transformer(TEST_CONFIG)
captured_temps = []
def mock_call(self, tokens, start_pos, temperature, **kwargs):
captured_temps.append(float(temperature.item()))
return Tensor([[42]])
with patch.object(Transformer, '__call__', mock_call):
gen = model.generate([1, 2, 3], temperature=0.6)
next(gen)
self.assertAlmostEqual(captured_temps[-1], 0.6, places=5)
if __name__ == '__main__':
unittest.main()