Files
AstrAI/tests/module/test_forward_configs.py
T
ViperEkura a317a4756b refactor: stateless MoE routing with grouped dispatch
- replace per-expert mask scan with sort+bincount grouped dispatch
- carry router stats in forward output instead of module state
- keep MoE diagnostics working under DDP/FSDP wrappers
- remove unused _load_balancing_loss helper
2026-08-05 18:42:12 +08:00

389 lines
11 KiB
Python

import pytest
import torch
from astrai.model.components.mlp import MLP, DeepSeekMoE
from astrai.model.transformer import AutoRegressiveLM
from tests.helpers import TINY_CONFIG
CONFIGS = [
pytest.param(
{**TINY_CONFIG, "attn_type": "gqa", "ffn_type": "mlp"},
id="gqa_mlp",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "mla",
"ffn_type": "mlp",
"kv_lora_rank": 4,
"qk_nope_head_dim": 2,
"qk_rope_head_dim": 2,
},
id="mla_mlp",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"topk_method": "greedy",
},
id="gqa_moe",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"topk_method": "greedy",
"mlp_only_layers": [0],
},
id="gqa_moe_dense_first",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"topk_method": "greedy",
"decoder_sparse_step": 2,
},
id="gqa_moe_sparse_step",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"topk_method": "greedy",
"norm_topk_prob": True,
},
id="gqa_moe_norm_topk",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"topk_method": "greedy",
"moe_intermediate_size": 24,
"shared_expert_intermediate_size": 20,
},
id="gqa_moe_custom_intermediate",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "mlp",
"rope_theta": 100000.0,
},
id="gqa_rope_theta",
),
pytest.param(
{**TINY_CONFIG, "attn_type": "gqa", "ffn_type": "mlp", "use_qk_norm": True},
id="gqa_qk_norm",
),
pytest.param(
{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "mlp",
"tie_word_embeddings": True,
},
id="gqa_tie_word_embeddings",
),
]
@pytest.mark.parametrize("config_kwargs", CONFIGS)
def test_model_forward(config_kwargs, device):
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(**config_kwargs)
model = AutoRegressiveLM(config).to(device=device)
model.eval()
batch_size, seq_len = 2, 8
input_ids = torch.randint(
0, config.vocab_size, (batch_size, seq_len), device=device
)
with torch.no_grad():
output = model(input_ids)
assert "logits" in output
assert "hidden_states" in output
assert output["logits"].shape == (batch_size, seq_len, config.vocab_size)
assert output["hidden_states"].shape == (
batch_size,
seq_len,
config.hidden_size,
)
assert not torch.isnan(output["logits"]).any()
assert not torch.isnan(output["hidden_states"]).any()
@pytest.mark.parametrize("config_kwargs", CONFIGS)
def test_model_forward_with_padding(config_kwargs, device):
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(**config_kwargs)
model = AutoRegressiveLM(config).to(device=device)
model.eval()
batch_size, seq_len = 2, 8
input_ids = torch.randint(
0, config.vocab_size, (batch_size, seq_len), device=device
)
input_mask = torch.ones(batch_size, seq_len, dtype=torch.bool, device=device)
input_mask[:, 4:] = False
with torch.no_grad():
output = model(input_ids, input_mask=input_mask)
assert output["logits"].shape == (batch_size, seq_len, config.vocab_size)
assert not torch.isnan(output["logits"]).any()
def test_moe_per_layer_ffn_resolution():
"""Verify that mlp_only_layers and decoder_sparse_step resolve FFN types correctly."""
from astrai.config.model_config import AutoRegressiveLMConfig
# mlp_only_layers: first layer dense, rest MoE
config = AutoRegressiveLMConfig(
**{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"mlp_only_layers": [0],
}
)
model = AutoRegressiveLM(config)
assert isinstance(model.layers[0].mlp, MLP)
assert not isinstance(model.layers[0].mlp, DeepSeekMoE)
assert isinstance(model.layers[1].mlp, DeepSeekMoE)
# decoder_sparse_step=2: every other layer is MoE
config2 = AutoRegressiveLMConfig(
**{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"decoder_sparse_step": 2,
}
)
model2 = AutoRegressiveLM(config2)
# layer 0 (id=0): (0+1)%2=1 != 0 -> MLP
assert isinstance(model2.layers[0].mlp, MLP)
assert not isinstance(model2.layers[0].mlp, DeepSeekMoE)
# layer 1 (id=1): (1+1)%2=0 -> MoE
assert isinstance(model2.layers[1].mlp, DeepSeekMoE)
# decoder_sparse_step=1 (default): all layers MoE
config3 = AutoRegressiveLMConfig(
**{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
}
)
model3 = AutoRegressiveLM(config3)
for layer in model3.layers:
assert isinstance(layer.mlp, DeepSeekMoE)
def test_moe_custom_intermediate_shape():
"""Verify MoE uses custom intermediate sizes when specified."""
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(
**{
**TINY_CONFIG,
"attn_type": "gqa",
"ffn_type": "moe",
"n_routed_experts": 4,
"n_shared_experts": 1,
"n_activated_experts": 2,
"moe_intermediate_size": 24,
"shared_expert_intermediate_size": 20,
}
)
model = AutoRegressiveLM(config)
moe_layer = model.layers[0].mlp
assert isinstance(moe_layer, DeepSeekMoE)
# routed experts use moe_intermediate_size
for expert in moe_layer.routed_experts:
assert expert.up.weight.shape[0] == 24
assert expert.gate.weight.shape[0] == 24
assert expert.down.weight.shape[1] == 24
# shared experts use shared_expert_intermediate_size
for expert in moe_layer.shared_experts:
assert expert.up.weight.shape[0] == 20
assert expert.gate.weight.shape[0] == 20
assert expert.down.weight.shape[1] == 20
def test_moe_defaults_preserve_normalized_routing():
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(
**TINY_CONFIG,
ffn_type="moe",
n_routed_experts=4,
n_shared_experts=1,
n_activated_experts=2,
topk_method="greedy",
)
model = AutoRegressiveLM(config)
assert config.norm_topk_prob is True
assert model.layers[0].mlp.norm_topk_prob is True
def test_moe_router_stats_in_output_during_training():
"""Verify forward output carries per-layer router_stats in training mode."""
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(
**TINY_CONFIG,
ffn_type="moe",
n_routed_experts=4,
n_shared_experts=1,
n_activated_experts=2,
topk_method="greedy",
)
model = AutoRegressiveLM(config)
model.train()
input_ids = torch.randint(0, config.vocab_size, (2, 8))
with torch.enable_grad():
outputs = model(input_ids)
stats = outputs["router_stats"]
assert isinstance(stats, list)
assert len(stats) == config.num_hidden_layers
for s in stats:
assert s["probs"].shape == (2 * 8, 4) # (N, n_routed_experts)
assert s["topk_indices"].shape == (2 * 8, 2) # (N, n_activated_experts)
def test_moe_router_stats_absent_in_eval():
"""Verify no router_stats are emitted outside training."""
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(
**TINY_CONFIG,
ffn_type="moe",
n_routed_experts=4,
n_shared_experts=1,
n_activated_experts=2,
)
model = AutoRegressiveLM(config)
model.eval()
with torch.no_grad():
outputs = model(torch.randint(0, config.vocab_size, (2, 8)))
assert "router_stats" not in outputs
def test_no_router_stats_for_mlp_model():
"""Verify pure MLP models emit no router_stats and no aux_loss."""
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(**TINY_CONFIG, ffn_type="mlp")
model = AutoRegressiveLM(config)
model.train()
with torch.enable_grad():
outputs = model(torch.randint(0, config.vocab_size, (2, 8)))
assert "router_stats" not in outputs
assert "aux_loss" not in outputs
def test_moe_aux_loss_only_emitted_during_training():
from astrai.config.model_config import AutoRegressiveLMConfig
config = AutoRegressiveLMConfig(
**TINY_CONFIG,
ffn_type="moe",
n_routed_experts=4,
n_shared_experts=1,
n_activated_experts=2,
topk_method="greedy",
)
model = AutoRegressiveLM(config)
input_ids = torch.randint(0, config.vocab_size, (2, 8))
outputs = model(input_ids)
assert outputs["aux_loss"].ndim == 0
assert outputs["aux_loss"].requires_grad
assert torch.isfinite(outputs["aux_loss"])
with torch.no_grad():
outputs = model(input_ids)
assert "aux_loss" not in outputs
model.eval()
outputs = model(input_ids)
assert "aux_loss" not in outputs
def test_moe_component_forward_returns_ffn_output():
from astrai.model.components.mlp import DeepSeekMoE
moe = DeepSeekMoE(
dim=8,
dim_ffn=16,
n_routed_experts=4,
n_shared_experts=1,
n_activated_experts=2,
)
output = moe(torch.randn(2, 8, 8))
assert output["hidden_states"].shape == (2, 8, 8)
assert output["aux_loss"] is not None
@pytest.mark.parametrize("decoder_sparse_step", [0, -1])
def test_moe_rejects_invalid_decoder_sparse_step(decoder_sparse_step):
from pydantic import ValidationError
from astrai.config.model_config import AutoRegressiveLMConfig
with pytest.raises(ValidationError, match="decoder_sparse_step must be at least 1"):
AutoRegressiveLMConfig(
**TINY_CONFIG,
ffn_type="moe",
n_routed_experts=4,
n_activated_experts=2,
decoder_sparse_step=decoder_sparse_step,
)