ucxx::AmSendParams Struct Reference

Parameters controlling Active Message send behavior. More...

#include <typedefs.h>

Public Member Functions
void	setUserHeader (const void *data, size_t size)
	Set opaque user header bytes from raw pointer. More...
void	setUserHeader (std::string_view data)
	Convenience overload to set user header from string-like views. More...

Public Attributes
uint32_t	flags {UCP_AM_SEND_FLAG_REPLY}
	UCP AM send flags.
ucp_datatype_t	datatype {ucp_dt_make_contig(1)}
	Datatype used by ucp_am_send_nbx.
ucs_memory_type_t	memoryType {UCS_MEMORY_TYPE_HOST}
	Sender memory type hint.
AmSendMemoryTypePolicy	memoryTypePolicy
	Receiver allocation policy. More...
std::optional< AmReceiverCallbackInfo >	receiverCallbackInfo
	Optional receiver callback metadata. More...
std::vector< std::byte >	userHeader {}

Detailed Description

Parameters controlling Active Message send behavior.

This object is used by the extended Active Message API to expose UCX send knobs without breaking existing callers.

Member Function Documentation

setUserHeader() [1/2]

void ucxx::AmSendParams::setUserHeader ( const void *  data, size_t  size  )

inline

Set opaque user header bytes from raw pointer.

Parameters

[in]	data	pointer to input bytes, may be nullptr iff size == 0.
[in]	size	number of bytes in input.

setUserHeader() [2/2]

void ucxx::AmSendParams::setUserHeader ( std::string_view  data )

inline

Convenience overload to set user header from string-like views.

Parameters

[in]

data

view of opaque bytes.

Member Data Documentation

memoryTypePolicy

AmSendMemoryTypePolicy ucxx::AmSendParams::memoryTypePolicy

Initial value:

{
    AmSendMemoryTypePolicy::FallbackToHost}

Receiver allocation policy.

receiverCallbackInfo

std::optional<AmReceiverCallbackInfo> ucxx::AmSendParams::receiverCallbackInfo

Initial value:

{
    std::nullopt}

Optional receiver callback metadata.

userHeader

std::vector<std::byte> ucxx::AmSendParams::userHeader {}

Opaque user-defined header bytes. This is serialized into the AM header parameter of ucp_am_send_nbx, which is subject to transport-level size limits. For TCP, the default segment size is ~8 KiB (UCX_TCP_TX_SEG_SIZE / UCX_TCP_RX_SEG_SIZE). Headers that exceed the transport limit will cause a fatal UCX error. Keep user headers small (recommended < 4 KiB) or increase segment size env vars as needed.

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The documentation for this struct was generated from the following file:

• /__w/ucxx/ucxx/cpp/include/ucxx/typedefs.h