The --axis <axis spec>
option redefines the values in a benchmark's axis. It
applies to the benchmark created by the most recent --benchmark
argument, or
all benchmarks if it precedes all --benchmark
arguments (if any).
Valid axis specification follow the form:
<axis_name>=<value>
<axis_name>=[<value1>,<value2>,...]
<axis_name>=[<start>:<stop>]
<axis_name>=[<start>:<stop>:<stride>]
<axis_name>[<flags>]=<value>
<axis_name>[<flags>]=[<value1>,<value2>,...]
<axis_name>[<flags>]=[<start>:<stop>]
<axis_name>[<flags>]=[<start>:<stop>:<stride>]
Whitespace is ignored if the argument is quoted.
The axis type is taken from the benchmark definition. Some axes have additional restrictions:
- Numeric axes:
- A single value, explicit list of values, or strided range may be specified.
- For
int64
axes, thepower_of_two
flag is specified by adding[pow2]
after the axis name. - Values may differ from those defined in the benchmark.
- String axes:
- A single value or explicit list of values may be specified.
- Values may differ from those defined in the benchmark.
- Type axes:
- A single value or explicit list of values may be specified.
- Values MUST be a subset of the types defined in the benchmark.
- Values MUST match the input strings provided by
--list
(e.g.I32
forint
). - Provide a
nvbench::type_strings<T>
specialization to modify a custom type's input string.
Axis Type | Example | Example Result |
---|---|---|
Int64 | -a InputSize=12345 |
12345 |
Int64Pow2 | -a InputSize[pow2]=8 |
256 |
Float64 | -a Quality=0.5 |
0.5 |
String | -a RNG=Uniform |
"Uniform" |
Type | -a ValueType=I32 |
int32_t |
Axis Type | Example | Example Result |
---|---|---|
Int64 | -a InputSize=[1,2,3,4,5] |
1, 2, 3, 4, 5 |
Int64Pow2 | -a InputSize[pow2]=[4,6,8,10] |
16, 64, 256, 1024 |
Float64 | -a Quality=[0.5,0.75,1.0] |
0.5, 0.75, 1.0 |
String | -a RNG=[Uniform,Gaussian] |
"Uniform", "Gaussian" |
Type | -a ValueType=[U8,I32,F64] |
uint8_t , int32_t , double |
Axis Type | Example | Example Result |
---|---|---|
Int64 | -a InputSize=[2:10:2] |
2, 4, 6, 8, 10 |
Int64Pow2 | -a InputSize[pow2]=[2:10:2] |
4, 16, 64, 256, 1024 |
Float64 | -a Quality=[.5:1:.1] |
0.5, 0.6, 0.7, 0.8, 0.9, 1.0 |
String | [Not supported] | |
Type | [Not supported] |