Describe the issue
Description
We observed a performance regression in the SplitToSequence operator between ONNXRuntime v1.18.0 and v1.19.0.
Affected Operator
SplitToSequence
- Opset Version: 13
- Data Type: int64
- Regression: >10% slowdown
- Culprit Commit:
08ecf30e (confirmed via git bisect)
Test Case Details
SplitToSequence (int64, 2D tensor)
Input:
- Name:
input
- Shape:
[64, 56] (2D tensor)
- Data type: int64
- Total elements: 3,584
Output:
- Name:
output
- Type: Sequence of tensors
- Element type: int64
Attributes:
- Default split (no explicit axis or split attribute specified)
Performance:
- v1.18.0: baseline
- v1.19.0: +17% slower
Regression Magnitude
- SplitToSequence (int64): +17% slowdown
Culprit Commit
Git bisect identified the regression-introducing commit:
- Commit:
08ecf30e
- Version Range: v1.18.0 → v1.19.0
Additional Context
- The same commit (
08ecf30e) also caused regression in Add operator (float16)
- This suggests a common change affecting multiple operators
- SplitToSequence is a relatively uncommon operator that splits tensors into sequences
- The test case uses int64 data type with 2D input
To reproduce
To Reproduce
-
Download and unzip test.zip
-
Run benchmark:
python script.py ./splittosequence 1.18.0 1.19.0 # Expected: +17% regression
-
Compare the reported latencies between the two versions.
test.zip
Urgency
No response
Platform
Linux
OS Version
Ubuntu 24.04.3 LTS
ONNX Runtime Installation
Released Package
ONNX Runtime Version or Commit ID
08ecf30
ONNX Runtime API
Python
Architecture
X64
Execution Provider
Default CPU
Execution Provider Library Version
No response
Model File
No response
Is this a quantized model?
No
Describe the issue
Description
We observed a performance regression in the SplitToSequence operator between ONNXRuntime v1.18.0 and v1.19.0.
Affected Operator
SplitToSequence
08ecf30e(confirmed via git bisect)Test Case Details
SplitToSequence (int64, 2D tensor)
Input:
input[64, 56](2D tensor)Output:
outputAttributes:
Performance:
Regression Magnitude
Culprit Commit
Git bisect identified the regression-introducing commit:
08ecf30eAdditional Context
08ecf30e) also caused regression in Add operator (float16)To reproduce
To Reproduce
Download and unzip test.zip
Run benchmark:
python script.py ./splittosequence 1.18.0 1.19.0 # Expected: +17% regressionCompare the reported latencies between the two versions.
test.zip
Urgency
No response
Platform
Linux
OS Version
Ubuntu 24.04.3 LTS
ONNX Runtime Installation
Released Package
ONNX Runtime Version or Commit ID
08ecf30
ONNX Runtime API
Python
Architecture
X64
Execution Provider
Default CPU
Execution Provider Library Version
No response
Model File
No response
Is this a quantized model?
No