[backport] Fix CPU bin compression with categorical data. (#8809) (#8810)

* [backport] Fix CPU bin compression with categorical data. (#8809)

* Fix CPU bin compression with categorical data.

* The bug causes the maximum category to be lesser than 256 or the maximum number of bins when
the input data is dense.

* Avoid test symbol.
This commit is contained in:
Jiaming Yuan 2023-02-16 06:39:25 +08:00 committed by GitHub
parent f15a6d2b19
commit c22f6db4bf
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6 changed files with 49 additions and 20 deletions

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@ -46,7 +46,7 @@ void ColumnMatrix::InitStorage(GHistIndexMatrix const& gmat, double sparse_thres
feature_offsets_[fid] = accum_index;
}
SetTypeSize(gmat.max_num_bins);
SetTypeSize(gmat.MaxNumBinPerFeat());
auto storage_size =
feature_offsets_.back() * static_cast<std::underlying_type_t<BinTypeSize>>(bins_type_size_);
index_.resize(storage_size, 0);

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@ -20,13 +20,13 @@ GHistIndexMatrix::GHistIndexMatrix() : columns_{std::make_unique<common::ColumnM
GHistIndexMatrix::GHistIndexMatrix(DMatrix *p_fmat, bst_bin_t max_bins_per_feat,
double sparse_thresh, bool sorted_sketch, int32_t n_threads,
common::Span<float> hess) {
common::Span<float> hess)
: max_numeric_bins_per_feat{max_bins_per_feat} {
CHECK(p_fmat->SingleColBlock());
// We use sorted sketching for approx tree method since it's more efficient in
// computation time (but higher memory usage).
cut = common::SketchOnDMatrix(p_fmat, max_bins_per_feat, n_threads, sorted_sketch, hess);
max_num_bins = max_bins_per_feat;
const uint32_t nbins = cut.Ptrs().back();
hit_count.resize(nbins, 0);
hit_count_tloc_.resize(n_threads * nbins, 0);
@ -63,7 +63,7 @@ GHistIndexMatrix::GHistIndexMatrix(MetaInfo const &info, common::HistogramCuts &
: row_ptr(info.num_row_ + 1, 0),
hit_count(cuts.TotalBins(), 0),
cut{std::forward<common::HistogramCuts>(cuts)},
max_num_bins(max_bin_per_feat),
max_numeric_bins_per_feat(max_bin_per_feat),
isDense_{info.num_col_ * info.num_row_ == info.num_nonzero_} {}
#if !defined(XGBOOST_USE_CUDA)
@ -86,13 +86,13 @@ void GHistIndexMatrix::PushBatch(SparsePage const &batch, common::Span<FeatureTy
}
GHistIndexMatrix::GHistIndexMatrix(SparsePage const &batch, common::Span<FeatureType const> ft,
common::HistogramCuts const &cuts, int32_t max_bins_per_feat,
bool isDense, double sparse_thresh, int32_t n_threads) {
common::HistogramCuts cuts, int32_t max_bins_per_feat,
bool isDense, double sparse_thresh, int32_t n_threads)
: cut{std::move(cuts)},
max_numeric_bins_per_feat{max_bins_per_feat},
base_rowid{batch.base_rowid},
isDense_{isDense} {
CHECK_GE(n_threads, 1);
base_rowid = batch.base_rowid;
isDense_ = isDense;
cut = cuts;
max_num_bins = max_bins_per_feat;
CHECK_EQ(row_ptr.size(), 0);
// The number of threads is pegged to the batch size. If the OMP
// block is parallelized on anything other than the batch/block size,
@ -127,12 +127,13 @@ INSTANTIATION_PUSH(data::SparsePageAdapterBatch)
#undef INSTANTIATION_PUSH
void GHistIndexMatrix::ResizeIndex(const size_t n_index, const bool isDense) {
if ((max_num_bins - 1 <= static_cast<int>(std::numeric_limits<uint8_t>::max())) && isDense) {
if ((MaxNumBinPerFeat() - 1 <= static_cast<int>(std::numeric_limits<uint8_t>::max())) &&
isDense) {
// compress dense index to uint8
index.SetBinTypeSize(common::kUint8BinsTypeSize);
index.Resize((sizeof(uint8_t)) * n_index);
} else if ((max_num_bins - 1 > static_cast<int>(std::numeric_limits<uint8_t>::max()) &&
max_num_bins - 1 <= static_cast<int>(std::numeric_limits<uint16_t>::max())) &&
} else if ((MaxNumBinPerFeat() - 1 > static_cast<int>(std::numeric_limits<uint8_t>::max()) &&
MaxNumBinPerFeat() - 1 <= static_cast<int>(std::numeric_limits<uint16_t>::max())) &&
isDense) {
// compress dense index to uint16
index.SetBinTypeSize(common::kUint16BinsTypeSize);

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@ -65,7 +65,7 @@ void GetRowPtrFromEllpack(Context const* ctx, EllpackPageImpl const* page,
GHistIndexMatrix::GHistIndexMatrix(Context const* ctx, MetaInfo const& info,
EllpackPage const& in_page, BatchParam const& p)
: max_num_bins{p.max_bin} {
: max_numeric_bins_per_feat{p.max_bin} {
auto page = in_page.Impl();
isDense_ = page->is_dense;

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@ -133,11 +133,15 @@ class GHistIndexMatrix {
std::vector<size_t> hit_count;
/*! \brief The corresponding cuts */
common::HistogramCuts cut;
/*! \brief max_bin for each feature. */
bst_bin_t max_num_bins;
/** \brief max_bin for each feature. */
bst_bin_t max_numeric_bins_per_feat;
/*! \brief base row index for current page (used by external memory) */
size_t base_rowid{0};
bst_bin_t MaxNumBinPerFeat() const {
return std::max(static_cast<bst_bin_t>(cut.MaxCategory() + 1), max_numeric_bins_per_feat);
}
~GHistIndexMatrix();
/**
* \brief Constrcutor for SimpleDMatrix.
@ -160,7 +164,7 @@ class GHistIndexMatrix {
* \brief Constructor for external memory.
*/
GHistIndexMatrix(SparsePage const& page, common::Span<FeatureType const> ft,
common::HistogramCuts const& cuts, int32_t max_bins_per_feat, bool is_dense,
common::HistogramCuts cuts, int32_t max_bins_per_feat, bool is_dense,
double sparse_thresh, int32_t n_threads);
GHistIndexMatrix(); // also for ext mem, empty ctor so that we can read the cache back.

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@ -35,7 +35,7 @@ class GHistIndexRawFormat : public SparsePageFormat<GHistIndexMatrix> {
if (!fi->Read(&page->hit_count)) {
return false;
}
if (!fi->Read(&page->max_num_bins)) {
if (!fi->Read(&page->max_numeric_bins_per_feat)) {
return false;
}
if (!fi->Read(&page->base_rowid)) {
@ -76,8 +76,8 @@ class GHistIndexRawFormat : public SparsePageFormat<GHistIndexMatrix> {
page.hit_count.size() * sizeof(decltype(page.hit_count)::value_type) +
sizeof(uint64_t);
// max_bins, base row, is_dense
fo->Write(page.max_num_bins);
bytes += sizeof(page.max_num_bins);
fo->Write(page.max_numeric_bins_per_feat);
bytes += sizeof(page.max_numeric_bins_per_feat);
fo->Write(page.base_rowid);
bytes += sizeof(page.base_rowid);
fo->Write(page.IsDense());

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@ -68,6 +68,30 @@ TEST(GradientIndex, FromCategoricalBasic) {
}
}
TEST(GradientIndex, FromCategoricalLarge) {
size_t constexpr kRows = 1000, kCats = 512, kCols = 1;
bst_bin_t max_bins = 8;
auto x = GenerateRandomCategoricalSingleColumn(kRows, kCats);
auto m = GetDMatrixFromData(x, kRows, 1);
Context ctx;
auto &h_ft = m->Info().feature_types.HostVector();
h_ft.resize(kCols, FeatureType::kCategorical);
BatchParam p{max_bins, 0.8};
{
GHistIndexMatrix gidx(m.get(), max_bins, p.sparse_thresh, false, Context{}.Threads(), {});
ASSERT_TRUE(gidx.index.GetBinTypeSize() == common::kUint16BinsTypeSize);
}
{
for (auto const &page : m->GetBatches<GHistIndexMatrix>(p)) {
common::HistogramCuts cut = page.cut;
GHistIndexMatrix gidx{m->Info(), std::move(cut), max_bins};
ASSERT_EQ(gidx.MaxNumBinPerFeat(), kCats);
}
}
}
TEST(GradientIndex, PushBatch) {
size_t constexpr kRows = 64, kCols = 4;
bst_bin_t max_bins = 64;