Implement 1D Adaptive Workload Splitting in CPPScheduler
Resolves COMPMID-4649
Change-Id: I941d2f8a40737ff05c49f6695a42884731ef2dc9
Signed-off-by: Dana Zlotnik <dana.zlotnik@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/6656
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: SiCong Li <sicong.li@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/src/runtime/IScheduler.cpp b/src/runtime/IScheduler.cpp
index 004b8a4..1d068c9 100644
--- a/src/runtime/IScheduler.cpp
+++ b/src/runtime/IScheduler.cpp
@@ -25,6 +25,7 @@
#include "arm_compute/core/CPP/ICPPKernel.h"
#include "arm_compute/core/Error.h"
+#include "arm_compute/core/Log.h"
#include "arm_compute/core/Window.h"
#include "src/common/cpuinfo/CpuInfo.h"
#include "src/runtime/SchedulerUtils.h"
@@ -138,6 +139,9 @@
default:
ARM_COMPUTE_ERROR("Unknown strategy");
}
+ // Make sure the smallest window is larger than minimim workload size
+ num_windows = adjust_num_of_windows(max_window, hints.split_dimension(), num_windows, *kernel, cpu_info());
+
std::vector<IScheduler::Workload> workloads(num_windows);
for(unsigned int t = 0; t < num_windows; ++t)
{
@@ -171,4 +175,37 @@
run_workloads(workloads);
}
+std::size_t IScheduler::adjust_num_of_windows(const Window &window, std::size_t split_dimension, std::size_t init_num_windows, const ICPPKernel &kernel, const CPUInfo &cpu_info)
+{
+ // Mitigation of the narrow split issue, which occurs when the split dimension is too small to split (hence "narrow").
+ if(window.num_iterations(split_dimension) < init_num_windows )
+ {
+ auto recommended_split_dim = Window::DimX;
+ for(std::size_t dims = Window::DimY; dims <= Window::DimW; ++dims)
+ {
+ if(window.num_iterations(recommended_split_dim) < window.num_iterations(dims))
+ {
+ recommended_split_dim = dims;
+ }
+ }
+ ARM_COMPUTE_LOG_INFO_MSG_WITH_FORMAT_CORE("%lu dimension is not a suitable dimension to split the workload. Recommended: %lu recommended_split_dim", split_dimension,
+ recommended_split_dim);
+ }
+
+ for(auto t = init_num_windows; t > 0; --t) // Trying the highest number of windows ,init_num_windows, first
+ {
+ // Try splitting the workload into t, subject to each subworkload size <= mws.
+ if((window.num_iterations(split_dimension) / kernel.get_mws(cpu_info, t)) >= t)
+ {
+ if(t != init_num_windows)
+ {
+ ARM_COMPUTE_LOG_INFO_MSG_CORE("The scheduler is using a different thread count than the one assigned by the user.");
+ }
+ return t;
+ }
+ }
+ ARM_COMPUTE_LOG_INFO_MSG_CORE("The scheduler is using single thread instead of the thread count assigned by the user.");
+ return 1; // If the workload is so small that it can't be split, we should run a single thread
+}
+
} // namespace arm_compute