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Remove column major specialization. (#5755)

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Co-authored-by: Hyunsu Cho <chohyu01@cs.washington.edu>
This commit is contained in:
Jiaming Yuan
2020-06-05 16:19:14 +08:00
committed by GitHub
parent bd9d57f579
commit cacff9232a
10 changed files with 70 additions and 204 deletions
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56
src/data/ellpack_page.cu
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@@ -154,8 +154,8 @@ struct WriteCompressedEllpackFunctor {
// Here the data is already correctly ordered and simply needs to be compacted
// to remove missing data
template <typename AdapterBatchT>
void CopyDataRowMajor(const AdapterBatchT& batch, EllpackPageImpl* dst,
int device_idx, float missing) {
void CopyDataToEllpack(const AdapterBatchT& batch, EllpackPageImpl* dst,
int device_idx, float missing) {
// Some witchcraft happens here
// The goal is to copy valid elements out of the input to an ellpack matrix
// with a given row stride, using no extra working memory Standard stream
@@ -209,51 +209,6 @@ void CopyDataRowMajor(const AdapterBatchT& batch, EllpackPageImpl* dst,
});
}
template <typename AdapterT, typename AdapterBatchT>
void CopyDataColumnMajor(AdapterT* adapter, const AdapterBatchT& batch,
EllpackPageImpl* dst, float missing) {
// Step 1: Get the sizes of the input columns
dh::caching_device_vector<size_t> column_sizes(adapter->NumColumns(), 0);
auto d_column_sizes = column_sizes.data().get();
// Populate column sizes
dh::LaunchN(adapter->DeviceIdx(), batch.Size(), [=] __device__(size_t idx) {
const auto& e = batch.GetElement(idx);
atomicAdd(reinterpret_cast<unsigned long long*>( // NOLINT
&d_column_sizes[e.column_idx]),
static_cast<unsigned long long>(1)); // NOLINT
});
thrust::host_vector<size_t> host_column_sizes = column_sizes;
// Step 2: Iterate over columns, place elements in correct row, increment
// temporary row pointers
dh::caching_device_vector<size_t> temp_row_ptr(adapter->NumRows(), 0);
auto d_temp_row_ptr = temp_row_ptr.data().get();
auto row_stride = dst->row_stride;
size_t begin = 0;
auto device_accessor = dst->GetDeviceAccessor(adapter->DeviceIdx());
common::CompressedBufferWriter writer(device_accessor.NumSymbols());
auto d_compressed_buffer = dst->gidx_buffer.DevicePointer();
data::IsValidFunctor is_valid(missing);
for (auto size : host_column_sizes) {
size_t end = begin + size;
dh::LaunchN(adapter->DeviceIdx(), end - begin, [=] __device__(size_t idx) {
auto writer_non_const =
writer; // For some reason this variable gets captured as const
const auto& e = batch.GetElement(idx + begin);
if (!is_valid(e)) return;
size_t output_position =
e.row_idx * row_stride + d_temp_row_ptr[e.row_idx];
auto bin_idx = device_accessor.SearchBin(e.value, e.column_idx);
writer_non_const.AtomicWriteSymbol(d_compressed_buffer, bin_idx,
output_position);
d_temp_row_ptr[e.row_idx] += 1;
});
begin = end;
}
}
void WriteNullValues(EllpackPageImpl* dst, int device_idx,
common::Span<size_t> row_counts) {
// Write the null values
@@ -284,12 +239,7 @@ EllpackPageImpl::EllpackPageImpl(AdapterT* adapter, float missing, bool is_dense
*this = EllpackPageImpl(adapter->DeviceIdx(), cuts, is_dense, row_stride,
adapter->NumRows());
if (adapter->IsRowMajor()) {
CopyDataRowMajor(batch, this, adapter->DeviceIdx(), missing);
} else {
CopyDataColumnMajor(adapter, batch, this, missing);
}
CopyDataToEllpack(batch, this, adapter->DeviceIdx(), missing);
WriteNullValues(this, adapter->DeviceIdx(), row_counts_span);
}