unsloth/tests/studio/run_real_mlx_smoke.py
Long Yixing d918245834
Add MLX-aware public Unsloth trainer API (#6462)
* feat: add mlx public trainer api

* test: cover mlx public trainer api

* fix: preserve mlx epoch trainer configs

* fix: pass mlx warmup ratio through config

* fix: align mlx trainer dataset order

* fix: keep mlx chat templates import-light

* fix: infer mlx trainer context length

* fix: mirror cuda mlx context defaults

* fix: align mlx notebook trainer defaults

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* fix: keep mlx public helpers import-light

* refactor: reuse mlx optimizer normalization

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* fix: address mlx review feedback

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* fix: tighten mlx training argument parity

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* fix: align mlx trainer eos default

* Fix MLX trainer to accept DataCollatorForSeq2Seq and handle TokenizerWrapper in get_chat_template

* Trim redundant docstrings on internal MLX helpers

* MLX review fixes: Studio optimizer import-safe on non-MLX hosts, preserve explicit max_length, skip MLX tests before import

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* MLX review round 2: defer max_length to model context, optimizer alias fallback for older zoo, skip non-MLX test on missing GPU deps

* MLX review round 3: keep chat_templates importable without torch on MLX

* fix: preserve MLX trainer notebook shims

* fix: ignore CUDA tokenizer moves on MLX

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* fix: harden MLX trainer shims

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* fix: unwrap MLX scheduler enum args

* fix: coerce integral MLX epoch counts

* fix: spoof CUDA compatibility APIs on MLX

* fix: harden MLX notebook compatibility shims

* MLX: add torch.cuda.mem_get_info to the compatibility shim

Notebook memory cells call torch.cuda.mem_get_info()[0] directly (not gated by
is_available), so on MLX it raises without a shim. Return (free, total) bytes
from the MLX device stats, consistent with the other torch.cuda compat helpers,
and add a matching assertion to the compat-API test.

* MLX: use active memory for mem_get_info; fix BatchEncoding.to keyword device

Address review on the MLX compatibility shim:
- torch.cuda.mem_get_info() now derives free bytes from current active MLX
  memory instead of the peak high-water mark, so a capacity check stays
  accurate after a transient spike or a prior run.
- BatchEncoding.to(device=...) passed by keyword no longer forwards a positional
  None alongside the keyword (which raised "multiple values for 'device'"), so
  non-CUDA keyword moves like .to(device="cpu") delegate correctly.

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* MLX: accept preserve_dataset_order; stub RL trainers with a clear error

Two fixes so unmigrated notebooks behave predictably on MLX (torch present):

- preserve_dataset_order is a real MLXTrainingConfig field but was missing from
  the extra-argument allowlist, so passing it (as a config or trainer kwarg)
  could be rejected as unknown on a zoo without the field. Add it to
  _MLX_IMPLEMENTED_EXTRA_ARGUMENTS so the documented no-shuffle path is reachable.

- GRPO/DPO/ORPO (and KTO/PPO/Reward) have no MLX trainer yet. Retarget the ones
  the installed trl exposes to a stub that raises a clear 'not supported on MLX'
  error instead of importing the real torch/CUDA trainer and crashing deep
  inside it. Only existing trainers are retargeted (no invented attributes),
  idempotent across re-imports.

* MLX: make RL-trainer stubbing import-safe; back current-memory APIs with active memory

Address review on the MLX shims:
- The RL-trainer stub loop probed trl with getattr(_trl, name), which triggers
  trl's lazy trainer import and pulls torch -- that can crash import unsloth on a
  torch-free MLX install just to check existence. Decide what to stub from
  trl.__all__ + already-materialized attrs (vars) instead; never resolve the real
  trainer. All trl trainer names are in __all__, so they are still stubbed (even
  torch-free), and the probe no longer imports torch.
- torch.cuda.memory_reserved / memory_allocated (the current, non-max APIs) were
  aliased to peak max_memory_reserved. Back them with current active MLX memory so
  cleanup / capacity checks see live usage; max_* keep the peak high-water mark.

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* MLX: keep TRL's SFTConfig epoch default under the trl.SFTConfig alias

Unmigrated notebooks import SFTConfig from trl, which the MLX build aliases to
the public training-args class. TRL/HF SFTConfig defaults to num_train_epochs=3
(max_steps=-1); the native MLX config defaults to max_steps=60. So an SFTConfig
built without an explicit length silently ran 60 MLX steps instead of TRL's 3
epochs under the alias. Alias trl.SFTConfig to a thin subclass that seeds the
TRL epoch default only when neither max_steps nor num_train_epochs is given;
explicit lengths pass through untouched, and the native public args class keeps
its MLX default. Epoch mode is supported by the MLX trainer.

* MLX CI: keep the GGUF reload smoke under the job timeout

The RELOAD-GGUF-via-llama-cli step timed out at 300s. BF16 GGUF decode is
CPU-bound on the macOS runner (~10s+/token), so generating 24 tokens landed
right on the 300s cliff and killed the process. This step is a save/reload
integrity smoke (it only needs a few chars of output), so the token count is
incidental: generate 8 tokens with explicit threads and a small headroom on the
subprocess timeout, all env-tunable (UNSLOTH_GGUF_RELOAD_N / _THREADS /
_TIMEOUT). Cuts the reload well under the 25 minute job budget.

* MLX: broaden trainer stubs, real peak-memory reset, fix shim tests

Address review on the MLX public API:
- The SFTConfig identity tests asserted trl.SFTConfig is UnslothTrainingArguments,
  but the alias now points at the _MLXSFTConfig subclass that preserves TRL's
  epoch default, so the MLX suite failed before testing the shim. Assert
  issubclass instead.
- torch.cuda.reset_peak_memory_stats was a no-op, so max_memory_reserved kept
  earlier model-load peaks across a scoped run. Wire it to mx.reset_peak_memory
  with the same core/metal fallback used for the reads.
- The unsupported-trainer stubs were a fixed list, so trainers outside it (a
  newer RLOOTrainer) still routed to the real torch trainer. Derive the set from
  trl.__all__ (every non-SFT *Trainer) so all non-SFT surfaces fail with a clear
  MLX message; names come from __all__ so trl is never resolved.
- The non-MLX export smoke skipped only on missing bitsandbytes/triton; other
  absent GPU deps (numpy/torch/unsloth-zoo, or _gpu_init re-raising ImportError)
  made it fail on CPU hosts. Skip on any ImportError.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* fix: keep MLX notebook compatibility minimal

* MLX CI: force CPU + small context for the GGUF reload smoke

The RELOAD-GGUF-via-llama-cli step timed out even at 8 tokens (>420s), so it is a
fixed hang, not per-token cost: on the paravirtual macOS runner GPU llama.cpp's
Metal backend stalls, and the gemma3 GGUF advertises a 32768 context that llama-cli
would otherwise fully allocate. Run llama-cli CPU-only (-ngl 0) with a small context
(-c 256); keep generation short. All env-tunable (UNSLOTH_GGUF_RELOAD_NGL / _CTX /
_N / _THREADS / _TIMEOUT). Also print llama.cpp's partial stdout/stderr on timeout so
a future hang is diagnosable instead of an opaque TimeoutExpired.

* MLX CI: export the reload-smoke GGUF as q8_0, not bf16

The GGUF reload via llama-cli timed out on the runner even CPU-only with a tiny
context and 8 tokens. Root cause is the format, not the flags: the smoke exported
quantization_method='not_quantized', which maps to a bf16 GGUF, and llama.cpp's
bf16 CPU decode is unusably slow on the paravirtual macOS runner. Export q8_0
(fast_quantized, the exporter default and what users deploy) instead -- llama.cpp
has optimized q8_0 CPU kernels, so the fresh-process reload loads and generates in
seconds. The reload stays CPU-only (-ngl 0) with a small context.

* test: clear TRL shim before availability check

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Daniel Han <danielhanchen@gmail.com>
Co-authored-by: Lee Jackson <130007945+Imagineer99@users.noreply.github.com>
Co-authored-by: imagineer99 <samleejackson0@gmail.com>
2026-07-02 23:02:26 +01:00

673 lines
24 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved.
"""End-to-end MLX smoke test on real Apple Silicon (multi-process driver).
`train` overfits gemma-3-270m-it on one row for 30 steps and saves
lora/merged_16bit/gguf; `reload` reopens each format in a fresh process.
GGUF + LoRA reload fixes land in unslothai/unsloth-zoo#627. Metal's
reduction-order nondeterminism makes loss assertions bounds, not exact.
Apple-Silicon only; invoked from .github/workflows/mlx-ci.yml.
"""
from __future__ import annotations
import argparse
import json
import math
import os
import random as _random
import resource
import subprocess
import sys
import time
from pathlib import Path
import numpy as np
SEED = 3407
TRAIN_TEXT = "<<HELLO!!>> My name is Unsloth!"
PROMPT = "<<HELLO!!>> My name is "
EXPECT_IN_OUTPUT = "Unsloth"
MODEL_NAME = "unsloth/gemma-3-270m-it"
# ---------------------------------------------------------------------------
# Determinism + telemetry helpers
# ---------------------------------------------------------------------------
def _seed_everything() -> None:
_random.seed(SEED)
np.random.seed(SEED)
import mlx.core as mx
mx.random.seed(SEED)
def _peak_gpu_gb() -> float:
import mlx.core as mx
if not mx.metal.is_available():
return 0.0
# Newer MLX moved get_peak_memory to top-level; fall back to mx.metal.
getter = getattr(mx, "get_peak_memory", None) or getattr(mx.metal, "get_peak_memory", None)
if getter is None:
return 0.0
try:
return float(getter()) / (1024**3)
except Exception:
return 0.0
def _peak_rss_gb() -> float:
"""Peak RSS for this process (macOS getrusage = bytes, Linux = KB)."""
rss = resource.getrusage(resource.RUSAGE_SELF).ru_maxrss
if sys.platform == "darwin":
return float(rss) / (1024**3)
return float(rss) / (1024**2)
class Phase:
"""Wall-clock + memory tracker for a named phase; records into a metrics dict."""
def __init__(self, name: str, metrics: dict):
self.name = name
self.metrics = metrics
def __enter__(self):
self._t0 = time.perf_counter()
print(f"\n=== phase:{self.name} START ===", flush = True)
return self
def __exit__(self, exc_type, exc, tb):
elapsed = time.perf_counter() - self._t0
peak_gpu = _peak_gpu_gb()
peak_rss = _peak_rss_gb()
self.metrics.setdefault("phases", {})[self.name] = {
"elapsed_seconds": round(elapsed, 3),
"peak_gpu_gb": round(peak_gpu, 3),
"peak_rss_gb": round(peak_rss, 3),
"ok": exc_type is None,
}
status = "OK" if exc_type is None else f"FAIL ({exc_type.__name__})"
print(
f"=== phase:{self.name} {status} elapsed={elapsed:.2f}s "
f"peak_gpu={peak_gpu:.2f}GB peak_rss={peak_rss:.2f}GB ===",
flush = True,
)
return False # don't swallow exceptions
def _compute_loss_and_grad_norm(model, tokenizer, text: str) -> tuple[float, float]:
"""One fwd+bwd of next-token CE on `text`. Returns (loss, ||grad||_2)."""
import mlx.core as mx
import mlx.nn as nn
from mlx.utils import tree_flatten
# Match Studio's text dataset path: no EOS appended behind the user's back.
ids = list(tokenizer.encode(text))
if len(ids) < 2:
raise RuntimeError(f"text too short to compute loss: {len(ids)} tokens")
inputs = mx.array([ids[:-1]], dtype = mx.int32)
targets = mx.array([ids[1:]], dtype = mx.int32)
def loss_fn(m):
logits = m(inputs)
return nn.losses.cross_entropy(logits, targets, reduction = "mean")
loss_and_grad = nn.value_and_grad(model, loss_fn)
loss_val, grad = loss_and_grad(model)
norm_sq = mx.array(0.0, dtype = mx.float32)
for _name, value in tree_flatten(grad):
v = value.astype(mx.float32)
norm_sq = norm_sq + mx.sum(v * v)
return float(loss_val.item()), float(mx.sqrt(norm_sq).item())
def _teacher_forced_completion_loss(model, tokenizer, prompt: str, completion: str) -> float:
"""Mean teacher-forced next-token CE on `completion` given `prompt`.
Decouples the memorisation check from flaky greedy-decode geometry:
asserts *what* the model memorised, not just that loss is low.
"""
import mlx.core as mx
import mlx.nn as nn
prompt_ids = list(tokenizer.encode(prompt))
full_ids = list(tokenizer.encode(prompt + completion))
if len(full_ids) <= len(prompt_ids):
raise RuntimeError(
f"completion {completion!r} tokenises to zero new tokens after "
f"{prompt!r}; check tokenizer / chat template."
)
inputs = mx.array([full_ids[:-1]], dtype = mx.int32)
targets = mx.array([full_ids[1:]], dtype = mx.int32)
logits = model(inputs)
# logits at position i predict targets[i]; completion starts at len(prompt_ids)-1.
start = len(prompt_ids) - 1
completion_logits = logits[:, start:, :]
completion_targets = targets[:, start:]
loss = nn.losses.cross_entropy(completion_logits, completion_targets, reduction = "mean")
return float(loss.item())
def _write_metrics(path: Path, metrics: dict) -> None:
path.write_text(json.dumps(metrics, indent = 2, default = str))
print(f"\n[metrics] wrote {path}", flush = True)
print(json.dumps(metrics, indent = 2, default = str), flush = True)
# ---------------------------------------------------------------------------
# `train` subcommand
# ---------------------------------------------------------------------------
def cmd_train(args) -> int:
_seed_everything()
metrics: dict = {
"subcommand": "train",
"seed": SEED,
"model": MODEL_NAME,
"train_text": TRAIN_TEXT,
"prompt": PROMPT,
"phases": {},
}
workdir = Path(args.workdir).resolve()
workdir.mkdir(parents = True, exist_ok = True)
import mlx.core as mx
from unsloth_zoo.mlx.loader import FastMLXModel
from unsloth_zoo.mlx.trainer import MLXTrainer, MLXTrainingConfig
hf_token = os.environ.get("HF_TOKEN") or None
with Phase("load_base", metrics):
model, tokenizer = FastMLXModel.from_pretrained(
MODEL_NAME,
load_in_4bit = False,
dtype = "float16",
text_only = True,
max_seq_length = 128,
random_state = SEED,
token = hf_token,
trust_remote_code = False,
)
metrics["base_src_path"] = str(getattr(model, "_src_path", "") or "")
mx.random.seed(SEED)
with Phase("apply_lora", metrics):
# Full q/k/v/o + gate/up/down set: q/k/v/o alone couldn't memorize
# the row, the MLP projections add the needed capacity.
model = FastMLXModel.get_peft_model(
model,
r = 8,
lora_alpha = 16,
lora_dropout = 0.0,
target_modules = [
"q_proj",
"k_proj",
"v_proj",
"o_proj",
"gate_proj",
"up_proj",
"down_proj",
],
use_gradient_checkpointing = False,
random_state = SEED,
finetune_language_layers = True,
finetune_attention_modules = True,
finetune_mlp_modules = True,
)
with Phase("pre_train_grad_probe", metrics):
pre_loss, pre_norm = _compute_loss_and_grad_norm(model, tokenizer, TRAIN_TEXT)
metrics["pre_train_loss"] = round(pre_loss, 4)
metrics["pre_train_grad_norm"] = round(pre_norm, 4)
assert math.isfinite(pre_loss) and math.isfinite(pre_norm) and pre_norm > 0
losses_per_step: list[float] = []
with Phase("train", metrics):
config = MLXTrainingConfig(
per_device_train_batch_size = 2,
gradient_accumulation_steps = 3,
# PR #5498 sweep: 7 steps too few; 30 makes every seed converge.
max_steps = 30,
learning_rate = 1e-3,
warmup_steps = 0,
lr_scheduler_type = "constant",
optim = "adamw",
weight_decay = 0.0,
# Pin the elementwise clip (value=1.0, norm disabled) to match the
# 13-seed-tested fixture; explicit value overrides zoo's MLX default.
max_grad_norm = 0.0,
max_grad_value = 1.0,
logging_steps = 1,
max_seq_length = 64,
seed = SEED,
use_cce = False,
compile = False,
gradient_checkpointing = False,
output_dir = str(workdir / "trainer_outputs"),
save_steps = 0,
eval_steps = 0,
dataset_text_field = "text",
)
trainer = MLXTrainer(
model = model,
tokenizer = tokenizer,
train_dataset = [{"text": TRAIN_TEXT}] * 64,
args = config,
)
def _on_step(
step,
total,
loss,
lr,
tok_s,
peak_gb,
elapsed,
num_tokens,
grad_norm = None,
):
losses_per_step.append(round(float(loss), 4))
grad_text = f" grad={grad_norm:.4f}" if grad_norm is not None else ""
print(
f" step {step}/{total} loss={loss:.4f} lr={lr:.2e} "
f"tok/s={tok_s:.0f} peak={peak_gb:.2f}GB{grad_text}",
flush = True,
)
trainer.add_step_callback(_on_step)
train_result = trainer.train()
metrics["losses_per_step"] = losses_per_step
metrics["train_summary"] = {
k: train_result[k]
for k in (
"train_loss",
"train_runtime",
"train_steps",
"trained_tokens",
"train_samples_per_second",
"compile_enabled",
"patch_mode",
)
if k in train_result
}
# logging_steps=1 + max_steps=N -> N callbacks; gate auto-follows max_steps.
expected_logged_steps = int(config.max_steps)
assert (
len(losses_per_step) == expected_logged_steps
), f"expected {expected_logged_steps} logged steps, got {losses_per_step}"
if "train_steps" in train_result:
assert int(train_result["train_steps"]) == expected_logged_steps, (
f"expected train_steps={expected_logged_steps}, got " f"{train_result['train_steps']}"
)
for i, l in enumerate(losses_per_step):
# Allow exact 0.0: fp16 loss underflows once the LoRA memorises the
# row (~step 10); that's success, so the lower bound is >= 0 not > 0.
assert math.isfinite(l) and 0 <= l < 50, f"step {i+1} loss bad: {l}"
assert (
losses_per_step[-1] < losses_per_step[0] * 1.1
), f"loss diverged: {losses_per_step[0]} -> {losses_per_step[-1]}"
with Phase("post_train_grad_probe", metrics):
post_loss, post_norm = _compute_loss_and_grad_norm(model, tokenizer, TRAIN_TEXT)
metrics["post_train_loss"] = round(post_loss, 4)
metrics["post_train_grad_norm"] = round(post_norm, 4)
assert post_loss < pre_loss, f"post {post_loss} >= pre {pre_loss}"
# Memorisation gate: every converging (clip, bc, seed) config in the
# 13-seed sweep hit post_train_loss <= 0.05, so 0.1 is a robust bound.
assert post_loss < 0.1, (
f"post_train_loss={post_loss:.4f} >= 0.1 -- training did not "
"memorise the single training row in 30 steps. Trainer "
"regression suspected."
)
from mlx_lm import generate
with Phase("inference_in_memory", metrics):
model.eval()
in_mem_out = generate(
model,
tokenizer,
prompt = PROMPT,
max_tokens = 48,
verbose = False,
)
metrics["in_memory_generation"] = in_mem_out
# Soft greedy-decode metric only (46-77% of seeds): fp16 + MLX generate
# noises the first token. The teacher-forced check below is load-bearing.
metrics["in_memory_generation_has_expected"] = EXPECT_IN_OUTPUT in in_mem_out
if EXPECT_IN_OUTPUT not in in_mem_out:
print(
f" [INFO] greedy decode did not contain {EXPECT_IN_OUTPUT!r} "
f"(post_train_loss={post_loss:.4f}, completion={in_mem_out!r}). "
"Hard gate is the teacher-forced completion-loss check below.",
flush = True,
)
# Hard check: teacher-forced loss on the trained completion bypasses
# greedy-decode fp16 fragility. 13/13 measured configs reached < 1e-3,
# so this gate is deterministic across (seed, clip, bc).
completion_loss = _teacher_forced_completion_loss(
model, tokenizer, PROMPT, EXPECT_IN_OUTPUT + "!"
)
metrics["in_memory_completion_teacher_forced_loss"] = round(completion_loss, 6)
assert completion_loss < 0.5, (
f"teacher-forced completion loss {completion_loss:.4f} >= 0.5: "
f"the LoRA did not memorise {EXPECT_IN_OUTPUT + '!'!r} after "
f"{PROMPT!r} (post_train_loss={post_loss:.4f}). Trainer regression "
"suspected -- check unsloth_zoo MLX trainer gradient clipping / "
"optimizer defaults vs torch.optim.AdamW."
)
# unsloth-zoo#627 fixed from_pretrained(lora_dir) so the cold-start
# reload below works on the saved adapter dir directly.
lora_dir = workdir / "lora"
with Phase("save_lora", metrics):
model.save_pretrained_merged(
str(lora_dir),
tokenizer = tokenizer,
save_method = "lora",
)
metrics["lora_dir"] = str(lora_dir)
assert (lora_dir / "adapters.safetensors").exists()
assert (lora_dir / "adapter_config.json").exists()
# Save merged_16bit (full HF directory)
merged_dir = workdir / "merged_16bit"
with Phase("save_merged_16bit", metrics):
model.save_pretrained_merged(
str(merged_dir),
tokenizer = tokenizer,
save_method = "merged_16bit",
)
metrics["merged_dir"] = str(merged_dir)
assert any(merged_dir.glob("*.safetensors"))
# Save GGUF (best-effort). For some models (e.g. gemma-3-270m-it)
# llama.cpp's convert_hf_to_gguf asserts on the tokenizer vocab -- an
# llama.cpp limitation, not an unsloth_zoo bug. Soft-skip with a recorded
# reason so the LoRA + merged_16bit assertions still gate the PR.
gguf_dir = workdir / "gguf"
metrics["gguf_supported"] = False
metrics["gguf_skip_reason"] = None
metrics["gguf_dir"] = str(gguf_dir)
with Phase("save_gguf", metrics):
try:
# q8_0 (the exporter default), not bf16: llama.cpp has optimized q8_0
# CPU kernels, whereas bf16 CPU decode is unusably slow on the runner
# and made the fresh-process llama-cli reload below time out. q8_0 is
# also what users deploy by default.
model.save_pretrained_gguf(
str(gguf_dir),
tokenizer = tokenizer,
quantization_method = "fast_quantized",
)
gguf_files = sorted(gguf_dir.glob("*.gguf"))
if not gguf_files:
raise RuntimeError(f"no .gguf produced in {gguf_dir}")
metrics["gguf_supported"] = True
metrics["gguf_files"] = [p.name for p in gguf_files]
except Exception as e:
err_text = f"{type(e).__name__}: {e}"
if "AssertionError" in err_text or "tokenizer.vocab" in err_text:
metrics["gguf_skip_reason"] = (
f"llama.cpp convert_hf_to_gguf asserted on tokenizer "
f"vocab for {MODEL_NAME} (max(vocab IDs) >= "
f"vocab_size). Downstream llama.cpp limitation, not "
f"unsloth_zoo. Underlying error: {err_text}"
)
else:
metrics["gguf_skip_reason"] = err_text
print(f" GGUF SKIPPED: {metrics['gguf_skip_reason']}", flush = True)
metrics["final_peak_gpu_gb"] = round(_peak_gpu_gb(), 3)
metrics["final_peak_rss_gb"] = round(_peak_rss_gb(), 3)
_write_metrics(workdir / "train_metrics.json", metrics)
return 0
# ---------------------------------------------------------------------------
# `reload` subcommand (fresh process per format)
# ---------------------------------------------------------------------------
def cmd_reload(args) -> int:
_seed_everything()
save_dir = Path(args.dir).resolve()
if not save_dir.exists():
raise SystemExit(f"reload dir not found: {save_dir}")
metrics: dict = {
"subcommand": "reload",
"format": args.format,
"dir": str(save_dir),
"phases": {},
}
if args.format == "gguf":
return _reload_gguf(save_dir, metrics)
import mlx.core as mx
from unsloth_zoo.mlx.loader import FastMLXModel
from mlx_lm import generate
hf_token = os.environ.get("HF_TOKEN") or None
with Phase(f"reload_{args.format}", metrics):
mx.random.seed(SEED)
m, t = FastMLXModel.from_pretrained(
str(save_dir),
load_in_4bit = False,
dtype = "float16",
text_only = True,
max_seq_length = 128,
random_state = SEED,
token = hf_token,
)
m.eval()
with Phase(f"generate_{args.format}", metrics):
out = generate(m, t, prompt = PROMPT, max_tokens = 48, verbose = False)
metrics["generation"] = out
print(f" [reload:{args.format}] output: {out!r}", flush = True)
# Save/reload invariant: reloaded teacher-forced loss on TRAIN_TEXT must
# match the in-memory post_train_loss. Robust to MLX's greedy-decode
# perturbation, which can flip the first token but not the loss.
train_metrics_path = save_dir.parent / "train_metrics.json"
in_mem_loss = None
in_mem_out = None
if train_metrics_path.exists():
try:
tm = json.loads(train_metrics_path.read_text())
in_mem_loss = tm.get("post_train_loss")
in_mem_out = tm.get("in_memory_generation")
except Exception:
in_mem_loss = None
metrics["in_memory_generation_ref"] = in_mem_out
metrics["in_memory_post_train_loss"] = in_mem_loss
metrics["reload_completion_matches_in_memory"] = in_mem_out is not None and out == in_mem_out
if isinstance(in_mem_loss, (int, float)) and math.isfinite(in_mem_loss):
reload_loss, _ = _compute_loss_and_grad_norm(m, t, TRAIN_TEXT)
metrics["reload_post_train_loss"] = round(reload_loss, 4)
# float16 round-trip is near-exact; 0.2 tolerates dequant noise.
assert abs(reload_loss - float(in_mem_loss)) < 0.2, (
f"reload {args.format!r} loss diverged from in-memory: "
f"reload={reload_loss:.4f}, in-memory={in_mem_loss:.4f}"
)
else:
# Fallback when train_metrics.json is missing: gate on non-empty output.
body = out.replace(PROMPT, "", 1).strip()
assert len(body) >= 4, (
f"reload {args.format!r} produced no usable output for " f"{PROMPT!r}: {out!r}"
)
metrics["final_peak_gpu_gb"] = round(_peak_gpu_gb(), 3)
metrics["final_peak_rss_gb"] = round(_peak_rss_gb(), 3)
_write_metrics(save_dir.parent / f"{args.format}_reload_metrics.json", metrics)
return 0
def _find_llama_cli() -> Path | None:
"""Locate the llama-cli binary save_pretrained_gguf built.
save_pretrained_gguf installs llama.cpp under unsloth_zoo's LLAMA_CPP_DEFAULT_DIR
($UNSLOTH_LLAMA_CPP_PATH or ~/.unsloth/llama.cpp), not the working directory, so
search there first and keep the CWD-relative layout as a fallback.
"""
bases: list[Path] = []
env_dir = os.environ.get("UNSLOTH_LLAMA_CPP_PATH")
if env_dir:
bases.append(Path(env_dir))
try:
from unsloth_zoo.llama_cpp import LLAMA_CPP_DEFAULT_DIR
bases.append(Path(LLAMA_CPP_DEFAULT_DIR))
except Exception:
bases.append(Path.home() / ".unsloth" / "llama.cpp")
bases.append(Path("llama.cpp"))
seen: set[Path] = set()
for base in bases:
if base in seen:
continue
seen.add(base)
for rel in ("llama-cli", "build/bin/llama-cli"):
cand = base / rel
if cand.is_file() and os.access(cand, os.X_OK):
# Absolute: a separator-less relative path would send subprocess
# to a PATH lookup instead of running the file.
return cand.resolve()
# Last resort: the binary may sit under an unexpected build subdir.
if base.is_dir():
for cand in sorted(base.glob("**/llama-cli")):
if cand.is_file() and os.access(cand, os.X_OK):
return cand.resolve()
return None
def _reload_gguf(save_dir: Path, metrics: dict) -> int:
llama_cli = _find_llama_cli()
if llama_cli is None:
raise SystemExit(
"llama-cli not found under $UNSLOTH_LLAMA_CPP_PATH, "
"~/.unsloth/llama.cpp, or ./llama.cpp"
)
gguf_files = sorted(save_dir.glob("*.gguf"))
if not gguf_files:
raise SystemExit(f"no .gguf files in {save_dir}")
gguf_path = gguf_files[0]
# Save/reload-integrity smoke (assert below only needs a few chars). The GGUF is
# exported q8_0 (see save_gguf) because llama.cpp bf16 CPU decode is unusably slow
# on the runner. Run CPU-only (-ngl 0), cap the context (-c 256, the model
# advertises 32768), and keep generation short; all env-tunable.
n_predict = os.environ.get("UNSLOTH_GGUF_RELOAD_N", "8")
n_threads = os.environ.get("UNSLOTH_GGUF_RELOAD_THREADS", str(os.cpu_count() or 4))
n_ctx = os.environ.get("UNSLOTH_GGUF_RELOAD_CTX", "256")
n_gpu_layers = os.environ.get("UNSLOTH_GGUF_RELOAD_NGL", "0")
reload_timeout = int(os.environ.get("UNSLOTH_GGUF_RELOAD_TIMEOUT", "420"))
argv = [
str(llama_cli),
"-m",
str(gguf_path),
"-p",
PROMPT,
"-n",
n_predict,
"-t",
n_threads,
"-c",
n_ctx,
"-ngl",
n_gpu_layers,
"--temp",
"0",
"--seed",
str(SEED),
"--no-warmup",
]
with Phase("reload_gguf", metrics):
try:
proc = subprocess.run(
argv,
capture_output = True,
text = True,
timeout = reload_timeout,
# Newer llama.cpp keeps llama-cli in chat mode; exit after one reply.
input = "/exit\n",
)
except subprocess.TimeoutExpired as exc:
def _decode(stream) -> str:
if isinstance(stream, bytes):
return stream.decode("utf-8", errors = "replace")
return stream or ""
print(f" [reload:gguf] TIMEOUT running: {' '.join(argv)}", flush = True)
print(f" [reload:gguf] TIMEOUT stdout:\n{_decode(exc.stdout)[:1000]}", flush = True)
print(f" [reload:gguf] TIMEOUT stderr:\n{_decode(exc.stderr)[:1000]}", flush = True)
raise
metrics["llama_cli_returncode"] = proc.returncode
metrics["generation"] = (proc.stdout or "")[:1500]
metrics["stderr_head"] = (proc.stderr or "")[:600]
print(f" [reload:gguf] stdout (head):\n{proc.stdout[:800]}", flush = True)
if proc.returncode != 0:
raise SystemExit(f"llama-cli exit {proc.returncode}; stderr head: {proc.stderr[:400]}")
# llama.cpp tokenises/samples differently than mlx_lm, so the GGUF
# completion needn't match. Require non-empty output to catch real
# save/reload corruption; record EXPECT_IN_OUTPUT without gating on it.
body = (proc.stdout or "").replace(PROMPT, "", 1).strip()
metrics["gguf_has_expected"] = EXPECT_IN_OUTPUT in (proc.stdout or "")
assert len(body) >= 4, (
f"GGUF reload produced no usable output for {PROMPT!r}: " f"{proc.stdout[:400]!r}"
)
metrics["final_peak_rss_gb"] = round(_peak_rss_gb(), 3)
_write_metrics(save_dir.parent / "gguf_reload_metrics.json", metrics)
return 0
# ---------------------------------------------------------------------------
# CLI
# ---------------------------------------------------------------------------
def main() -> int:
parser = argparse.ArgumentParser()
sub = parser.add_subparsers(dest = "cmd", required = True)
p_train = sub.add_parser("train")
p_train.add_argument("--workdir", required = True)
p_reload = sub.add_parser("reload")
p_reload.add_argument(
"--format",
required = True,
choices = ["lora", "merged", "gguf"],
)
p_reload.add_argument("--dir", required = True)
args = parser.parse_args()
if args.cmd == "train":
return cmd_train(args)
if args.cmd == "reload":
return cmd_reload(args)
return 1
if __name__ == "__main__":
sys.exit(main())