partitioning.hpp
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3  *
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16 
17 #pragma once
18 
19 #include <cudf/hashing.hpp>
21 #include <cudf/utilities/export.hpp>
23 
24 #include <rmm/cuda_stream_view.hpp>
25 
26 #include <memory>
27 #include <vector>
28 
29 namespace CUDF_EXPORT cudf {
40 enum class hash_id {
41  HASH_IDENTITY = 0,
43 };
44 
79 std::pair<std::unique_ptr<table>, std::vector<size_type>> partition(
80  table_view const& t,
81  column_view const& partition_map,
82  size_type num_partitions,
85 
106 std::pair<std::unique_ptr<table>, std::vector<size_type>> hash_partition(
107  table_view const& input,
108  std::vector<size_type> const& columns_to_hash,
109  int num_partitions,
110  hash_id hash_function = hash_id::HASH_MURMUR3,
111  uint32_t seed = DEFAULT_HASH_SEED,
114 
253 std::pair<std::unique_ptr<cudf::table>, std::vector<cudf::size_type>> round_robin_partition(
254  table_view const& input,
255  cudf::size_type num_partitions,
256  cudf::size_type start_partition = 0,
259  // end of group
261 } // namespace CUDF_EXPORT cudf
A non-owning, immutable view of device data as a column of elements, some of which may be null as ind...
A set of cudf::column_view's of the same size.
Definition: table_view.hpp:200
rmm::cuda_stream_view const get_default_stream()
Get the current default stream.
rmm::device_async_resource_ref get_current_device_resource_ref()
Get the current device memory resource reference.
cuda::mr::async_resource_ref< cuda::mr::device_accessible > device_async_resource_ref
hash_id
Identifies the hash function to be used in hash partitioning.
std::pair< std::unique_ptr< table >, std::vector< size_type > > hash_partition(table_view const &input, std::vector< size_type > const &columns_to_hash, int num_partitions, hash_id hash_function=hash_id::HASH_MURMUR3, uint32_t seed=DEFAULT_HASH_SEED, rmm::cuda_stream_view stream=cudf::get_default_stream(), rmm::device_async_resource_ref mr=cudf::get_current_device_resource_ref())
Partitions rows from the input table into multiple output tables.
std::pair< std::unique_ptr< cudf::table >, std::vector< cudf::size_type > > round_robin_partition(table_view const &input, cudf::size_type num_partitions, cudf::size_type start_partition=0, rmm::cuda_stream_view stream=cudf::get_default_stream(), rmm::device_async_resource_ref mr=cudf::get_current_device_resource_ref())
Round-robin partition.
std::pair< std::unique_ptr< table >, std::vector< size_type > > partition(table_view const &t, column_view const &partition_map, size_type num_partitions, rmm::cuda_stream_view stream=cudf::get_default_stream(), rmm::device_async_resource_ref mr=cudf::get_current_device_resource_ref())
Partitions rows of t according to the mapping specified by partition_map.
@ HASH_IDENTITY
Identity hash function that simply returns the key to be hashed.
@ HASH_MURMUR3
Murmur3 hash function.
int32_t size_type
Row index type for columns and tables.
Definition: types.hpp:95
cuDF interfaces
Definition: host_udf.hpp:39