Skip to content

fp8 kv cache support fix for torch.compile #22758

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 8 commits into from
Sep 16, 2025
Merged

fp8 kv cache support fix for torch.compile #22758

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
8 commits
Select commit Hold shift + click to select a range
164c0f3
fp8 kv cache support for fp4 llama 3.1 405B
Aug 12, 2025
c9e1469
minor fix for q_scale to be tensor fix
Aug 12, 2025
c29c2fd
lint error fix
Aug 14, 2025
6a25ff3
Merge remote-tracking branch 'origin/main' into fp8_kv_cache_fix_for_…
gshtras Sep 10, 2025
52d4c10
Merge branch 'main' into fp8_kv_cache_fix_for_torch_compile
gshtras Sep 10, 2025
5bc9d13
Merge branch 'main' into fp8_kv_cache_fix_for_torch_compile
gshtras Sep 12, 2025
810fec1
merge with main
Sep 16, 2025
bb5b672
Merge branch 'main' into fp8_kv_cache_fix_for_torch_compile
maleksan85 Sep 16, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 3 additions & 1 deletion vllm/model_executor/layers/quantization/kv_cache.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -125,7 +125,9 @@ def process_weights_after_loading(self, layer: torch.nn.Module) -> None:

# These are used in the final Attention.forward()
layer._q_scale.copy_(q_scale)
layer._q_scale_float = q_scale
layer._q_scale_float = q_scale.item() if isinstance(
q_scale, torch.Tensor) else q_scale

layer._prob_scale.copy_(prob_scale)
if layer.kv_cache_dtype == "fp8" and (q_scale == 1.0
or prob_scale == 1.0):
Expand Down
2 changes: 1 addition & 1 deletion vllm/v1/attention/backends/triton_attn.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -361,7 +361,7 @@ def forward(
key_cache = key_cache.view(self.fp8_dtype)
value_cache = value_cache.view(self.fp8_dtype)
num_tokens, num_heads, head_size = query.shape
assert layer._q_scale == 1.0, \
assert layer._q_scale_float == 1.0, \
"A non 1.0 q_scale is not currently supported."
if current_platform.is_cuda():
# Skip Q quantization on ROCm and XPU, enable this on cuda
Expand Down