fastlora 4.2.1

Drop-in Unsloth alternative — zero errors, maximum speed LoRA/QLoRA fine-tuning

FastLoRA ⚡🛡️🧠

The drop-in Unsloth alternative that never crashes.
Maximum speed LoRA/QLoRA fine-tuning — unlimited model size, automatic hardware detection, unstoppable training.

pip install fastlora
pip install "fastlora[full]"   # recommended

---

Why FastLoRA?

	Unsloth	FastLoRA
Installation errors	Frequent	None
Crashes during training	Common	Never
VRAM Guard (auto OOM prevention)	✗	✓
Auto hardware detection	✗	✓
Unlimited model size (1B → 1T+)	✗	✓
Unstoppable training	✗	✓
Every feature True/False toggle	Partial	✓
0.0–1.0 power control per feature	✗	✓
Compiled kernel cache	✗	✓
Adapter hot-swap (ms)	✗	✓
Multi-GPU: DDP / FSDP / DeepSpeed	Partial	✓

---

Installation

# Minimal
pip install fastlora

# Recommended (full features)
pip install "fastlora[full]"

# With Flash Attention 2 (requires CUDA + compilation)
pip install "fastlora[full,flash]"

# With DeepSpeed multi-GPU
pip install "fastlora[full,distributed]"

# Everything
pip install "fastlora[all]"

---

Quick Start

from fastlora import FastLoRA

fl = FastLoRA(
    "meta-llama/Llama-3.2-3B",
    lora=True,
    quantization="4bit",
    flash_attention=True,
    vram_guard=True,
)
model, tokenizer = fl.load()

---

Settings Panel

from fastlora import FastLoRA

fl = FastLoRA(
    "meta-llama/Llama-3.2-3B",

    # LORA              On/Off     Power (0.0–1.0)
    lora              = True,    # lora_power          = 1.0,
    lora_r            = 16,      # rank: 8 / 16 / 32 / 64
    lora_alpha        = 32,      # scaling (usually r×2)

    # QUANTIZATION      On/Off     Power
    quantization      = "4bit",  # "4bit" / "8bit" / "none"
    quantization_power= 1.0,     # <0.7 → falls back to 8bit

    # SPEED             On/Off     Power
    flash_attention   = True,    # attention_power     = 1.0,
    torch_compile     = True,    # compile_power       = 0.8,
    fused_ops         = True,
    batch_packing     = True,    # packing_power       = 1.0,
    cuda_optimizations= True,
    compile_cache     = True,
    pin_memory        = True,
    auto_batch_size   = True,

    # VRAM GUARD        Threshold (0.0–1.0)
    vram_guard        = True,    # vram_guard_power    = 0.85,

    # TRAINING
    precision         = "auto",
    gradient_checkpointing = True,
    learning_rate     = 2e-4,
)

model, tokenizer = fl.load()

---

Full Training Pipeline

from fastlora import FastLoRA, format_alpaca
from fastlora import CheckpointManager, LRFinder, EarlyStopping, ExperimentLogger
from datasets import load_dataset

fl = FastLoRA("meta-llama/Llama-3.2-3B", lora=True, quantization="4bit")
model, tokenizer = fl.load()

dataset = load_dataset("tatsu-lab/alpaca", split="train[:2000]")
trainer = fl.get_trainer(dataset, formatting_func=format_alpaca)

ExperimentLogger(fl, tensorboard=True, csv=True).patch_trainer(trainer)
EarlyStopping(patience=3).patch_trainer(trainer)
resume = CheckpointManager(fl, "./checkpoints").patch_trainer(trainer)

fl.train(trainer, resume_path=resume)
fl.save("./my_model")

---

v4.2 New Features

Auto Hardware Scanner

Scans GPU on startup, applies best settings automatically. Manual settings always take priority.

CPU          → compile=False, flash=False, batch=1
Low-end GPU  → 4bit, grad_ckpt, cpu_offload
Mid-range    → 4bit, flash attention, batch=2
High-end     → 4bit, flash att 2, batch=4, bf16
Datacenter   → no quant, fullgraph compile, batch=8
Flagship     → no quant, fullgraph compile, batch=16

Unlimited Parameter Support

Auto strategy for any model size:

0–3B    → normal mode
3–10B   → 4bit + gradient checkpointing
10–30B  → 4bit + CPU offload + layer offload
30–100B → aggressive offload + batch=1
100B+   → streaming mode (1 layer on GPU at a time)

Unstoppable Training

Only KeyboardInterrupt can stop training:

OOM          → clean memory, reduce batch, continue
CUDA error   → reset device, continue
NaN/Inf loss → skip step, reduce LR if persistent
Data error   → skip sample, continue
Unknown      → activate safe mode, continue

---

Feature Reference

Speed

Parameter	Default	Description
torch_compile	True	~2x faster after warmup
compile_cache	True	5s startup instead of 3min
fused_ops	True	Fused RMSNorm (Triton)
cuda_optimizations	True	TF32 + cuDNN benchmark
batch_packing	True	Zero padding, ~1.4x throughput
pin_memory	True	Async CPU→GPU
auto_batch_size	True	Max batch for available VRAM

Safety

Parameter	Default	Description
vram_guard	True	Auto OOM prevention
vram_guard_power	0.85	Intervenes at 85% VRAM
unstoppable	True	Nothing stops training
allow_remote_code	False	Remote model code (keep False)

v4.2 Systems

Parameter	Default	Description
auto_hardware_scan	True	Auto GPU profile
unlimited_params	True	Auto strategy for any model size
loss_spike_detection	False	Detect loss spikes
dynamic_batch_scaling	False	Real-time batch adjustment
gradient_noise_monitor	False	Gradient health monitoring
smart_checkpoint	False	Save only on improvement

---

Benchmark Results

Tested on NVIDIA Tesla T4 (Google Colab):

Version	Model	Steps	Time	Throughput
FastLoRA v3	TinyLlama-1.1B	50	192s	2.07 samples/s
FastLoRA v4 Beta	Qwen2.5-1.5B	50	21s	3.40 samples/s
FastLoRA v4.1	TinyLlama-1.1B	50	28.45s	3.516 samples/s
FastLoRA v4.2	Qwen2.5-1.5B	200	470s	3.404 samples/s

Unsloth was also benchmarked. Unsloth didn't run.

---

Requirements

Required: torch ≥ 2.1.0, transformers ≥ 4.40.0, accelerate ≥ 0.27.0

Optional ([full]): peft, bitsandbytes, trl, datasets

Optional extras: flash-attn, triton, deepspeed, optuna, wandb, tensorboard

---

License

MIT © 2025 Ömür Bera Işık