Allow users to control iteration via the concept of iteration spaces.

Changes in the work include:
- [x] Internally use linear_space for iterating
- [x] Simplify type and value iteration in `state_iterator::build_axis_configs`
- [x] Store the iteration space in `axes_metadata`
- [x] Expose `tie` and `user` spaces to user
- [x] Add tests for `linear`, `tie`, and `user`
- [x] Add examples for `tie` and `user`
This commit is contained in:
Robert Maynard
2022-01-31 08:56:48 -05:00
parent 9eed5ab9c3
commit 344878e9dc
18 changed files with 1369 additions and 175 deletions

View File

@@ -7,6 +7,7 @@ set(example_srcs
stream.cu
throughput.cu
auto_throughput.cu
custom_iteration_spaces.cu
)
# Metatarget for all examples:

View File

@@ -0,0 +1,247 @@
/*
* Copyright 2021 NVIDIA Corporation
*
* Licensed under the Apache License, Version 2.0 with the LLVM exception
* (the "License"); you may not use this file except in compliance with
* the License.
*
* You may obtain a copy of the License at
*
* http://llvm.org/foundation/relicensing/LICENSE.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <nvbench/nvbench.cuh>
// Grab some testing kernels from NVBench:
#include <nvbench/test_kernels.cuh>
// Thrust vectors simplify memory management:
#include <thrust/device_vector.h>
#include <random>
//==============================================================================
// Multiple parameters:
// Varies block_size and num_blocks while invoking a naive copy of 256 MiB worth
// of int32_t.
void copy_sweep_grid_shape(nvbench::state &state)
{
// Get current parameters:
const int block_size = static_cast<int>(state.get_int64("BlockSize"));
const int num_blocks = static_cast<int>(state.get_int64("NumBlocks"));
// Number of int32s in 256 MiB:
const std::size_t num_values = 256 * 1024 * 1024 / sizeof(nvbench::int32_t);
// Report throughput stats:
state.add_element_count(num_values);
state.add_global_memory_reads<nvbench::int32_t>(num_values);
state.add_global_memory_writes<nvbench::int32_t>(num_values);
// Allocate device memory:
thrust::device_vector<nvbench::int32_t> in(num_values, 0);
thrust::device_vector<nvbench::int32_t> out(num_values, 0);
state.exec(
[block_size,
num_blocks,
num_values,
in_ptr = thrust::raw_pointer_cast(in.data()),
out_ptr = thrust::raw_pointer_cast(out.data())](nvbench::launch &launch) {
nvbench::copy_kernel<<<num_blocks, block_size, 0, launch.get_stream()>>>(
in_ptr,
out_ptr,
num_values);
});
}
//==============================================================================
// Tied iteration space allows you to iterate two or more axes at the same
// time allowing for sparse exploration of the search space. Can also be used
// to test the diagonal of a square matrix
//
void tied_copy_sweep_grid_shape(nvbench::state &state)
{
copy_sweep_grid_shape(state);
}
NVBENCH_BENCH(tied_copy_sweep_grid_shape)
// Every power of two from 64->1024:
.add_int64_axis("BlockSize", {32,64,128,256})
.add_int64_axis("NumBlocks", {1024,512,256,128})
.tie_axes({"BlockSize", "NumBlocks"});
//==============================================================================
// under_diag:
// Custom iterator that only searches the `X` locations of two axi
// [- - - - X]
// [- - - X X]
// [- - X X X]
// [- X X X X]
// [X X X X X]
//
struct under_diag final : nvbench::user_axis_space
{
under_diag(std::vector<std::size_t> input_indices,
std::vector<std::size_t> output_indices)
: nvbench::user_axis_space(std::move(input_indices), std::move(output_indices))
{}
mutable std::size_t x_pos = 0;
mutable std::size_t y_pos = 0;
mutable std::size_t x_start = 0;
nvbench::detail::axis_space_iterator do_iter(axes_info info) const
{
// generate our increment function
auto adv_func = [&, info](std::size_t &inc_index,
std::size_t /*len*/) -> bool {
inc_index++;
x_pos++;
if (x_pos == info[0].size)
{
x_pos = ++x_start;
y_pos = x_start;
return true;
}
return false;
};
// our update function
std::vector<std::size_t> locs = m_output_indices;
auto diag_under =
[&, locs, info](std::size_t,
std::vector<nvbench::detail::axis_index> &indices) {
nvbench::detail::axis_index temp = info[0];
temp.index = x_pos;
indices[locs[0]] = temp;
temp = info[1];
temp.index = y_pos;
indices[locs[1]] = temp;
};
const size_t iteration_length = ((info[0].size * (info[1].size + 1)) / 2);
return nvbench::detail::make_space_iterator(2,
iteration_length,
adv_func,
diag_under);
}
std::size_t do_size(const axes_info &info) const
{
return ((info[0].size * (info[1].size + 1)) / 2);
}
std::size_t do_valid_count(const axes_info &info) const
{
return ((info[0].size * (info[1].size + 1)) / 2);
}
std::unique_ptr<nvbench::axis_space_base> do_clone() const
{
return std::make_unique<under_diag>(*this);
}
};
void user_copy_sweep_grid_shape(nvbench::state &state)
{
copy_sweep_grid_shape(state);
}
NVBENCH_BENCH(user_copy_sweep_grid_shape)
// Every power of two from 64->1024:
.add_int64_power_of_two_axis("BlockSize", nvbench::range(6, 10))
.add_int64_power_of_two_axis("NumBlocks", nvbench::range(6, 10))
.user_iteration_axes({"NumBlocks", "BlockSize"},
[](auto... args)
-> std::unique_ptr<nvbench::axis_space_base> {
return std::make_unique<under_diag>(args...);
});
//==============================================================================
// gauss:
// Custom iteration space that uses a gauss distribution to
// sample the points near the middle of the index space
//
struct gauss final : nvbench::user_axis_space
{
gauss(std::vector<std::size_t> input_indices,
std::vector<std::size_t> output_indices)
: nvbench::user_axis_space(std::move(input_indices), std::move(output_indices))
{}
nvbench::detail::axis_space_iterator do_iter(axes_info info) const
{
const double mid_point = static_cast<double>((info[0].size / 2));
std::random_device rd{};
std::mt19937 gen{rd()};
std::normal_distribution<> d{mid_point, 2};
const size_t iteration_length = info[0].size;
std::vector<std::size_t> gauss_indices(iteration_length);
for (auto &g : gauss_indices)
{
auto v = std::min(static_cast<double>(info[0].size), d(gen));
v = std::max(0.0, v);
g = static_cast<std::size_t>(v);
}
// our update function
std::vector<std::size_t> locs = m_output_indices;
auto gauss_func = [=](std::size_t index,
std::vector<nvbench::detail::axis_index> &indices) {
nvbench::detail::axis_index temp = info[0];
temp.index = gauss_indices[index];
indices[locs[0]] = temp;
};
return nvbench::detail::make_space_iterator(1,
iteration_length,
gauss_func);
}
std::size_t do_size(const axes_info &info) const { return info[0].size; }
std::size_t do_valid_count(const axes_info &info) const
{
return info[0].size;
}
std::unique_ptr<axis_space_base> do_clone() const
{
return std::make_unique<gauss>(*this);
}
};
//==============================================================================
// Dual parameter sweep:
void dual_float64_axis(nvbench::state &state)
{
const auto duration_A = state.get_float64("Duration_A");
const auto duration_B = state.get_float64("Duration_B");
state.exec([duration_A, duration_B](nvbench::launch &launch) {
nvbench::sleep_kernel<<<1, 1, 0, launch.get_stream()>>>(duration_A +
duration_B);
});
}
NVBENCH_BENCH(dual_float64_axis)
.add_float64_axis("Duration_A", nvbench::range(0., 1e-4, 1e-5))
.add_float64_axis("Duration_B", nvbench::range(0., 1e-4, 1e-5))
.user_iteration_axes({"Duration_A"},
[](auto... args)
-> std::unique_ptr<nvbench::axis_space_base> {
return std::make_unique<gauss>(args...);
})
.user_iteration_axes({"Duration_B"},
[](auto... args)
-> std::unique_ptr<nvbench::axis_space_base> {
return std::make_unique<gauss>(args...);
});