icexelloss commented on code in PR #13880:
URL: https://github.com/apache/arrow/pull/13880#discussion_r954254245
##########
cpp/src/arrow/compute/exec/asof_join_node.cc:
##########
@@ -137,18 +173,88 @@ struct MemoStore {
}
};
+// a specialized higher-performance variation of Hashing64 logic from
hash_join_node
+// the code here avoids recreating objects that are independent of each batch
processed
+class KeyHasher {
+ static constexpr int kMiniBatchLength = util::MiniBatch::kMiniBatchLength;
+
+ public:
+ explicit KeyHasher(const vec_col_index_t& indices)
+ : indices_(indices),
+ metadata_(indices.size()),
+ batch_(NULLPTR),
+ hashes_(),
+ ctx_(),
+ column_arrays_(),
+ stack_() {
+ ctx_.stack = &stack_;
+ column_arrays_.resize(indices.size());
+ }
+
+ Status Init(ExecContext* exec_context, const std::shared_ptr<arrow::Schema>&
schema) {
+ ctx_.hardware_flags = exec_context->cpu_info()->hardware_flags();
+ const auto& fields = schema->fields();
+ for (size_t k = 0; k < metadata_.size(); k++) {
+ ARROW_ASSIGN_OR_RAISE(metadata_[k],
+
ColumnMetadataFromDataType(fields[indices_[k]]->type()));
+ }
+ return stack_.Init(exec_context->memory_pool(),
+ 4 * kMiniBatchLength * sizeof(uint32_t));
Review Comment:
What does `4 * kMiniBatchLength * sizeof(uint32_t)` mean here and why pick
this value?
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
