Encapsulation of an I/O request, queues for requests and threads to process them. More...

Collaboration diagram for I/O Requests and Queues:

Classes
class	stxxl::disk_queues
	Encapsulates disk queues. More...

class	stxxl::linuxaio_queue
	Queue for linuxaio_file(s) More...

class	stxxl::linuxaio_request
	Request for an linuxaio_file. More...

class	stxxl::request
	Request object encapsulating basic properties like file and offset. More...

class	stxxl::request_interface
	Functional interface of a request. More...

class	stxxl::request_queue
	Interface of a request_queue to which requests can be added and canceled. More...

class	stxxl::request_queue_impl_1q
	Implementation of a local request queue having only one queue for both read and write requests, thus having only one thread. More...

class	stxxl::request_queue_impl_qwqr
	Implementation of a local request queue having two queues, one for read and one for write requests, thus having two threads. This is the default implementation. More...

class	stxxl::request_queue_impl_worker
	Implementation of request queue worker threads. Worker threads can be started by start_thread and stopped with stop_thread. The queue state is checked before termination and updated afterwards. More...

class	stxxl::request_with_state
	Request with completion state. More...

class	stxxl::request_with_waiters
	Request that is aware of threads waiting for it to complete. More...

class	stxxl::serving_request
	Request which serves an I/O by calling the synchronous routine of the file. More...

Macros
#define	STXXL_BLOCK_ALIGN 4096

Typedefs
typedef counting_ptr< request >	stxxl::request_ptr
	A reference counting pointer for `request`. More...

Functions
template<class RequestIterator >
std::iterator_traits < RequestIterator > ::difference_type	stxxl::cancel_all (RequestIterator reqs_begin, RequestIterator reqs_end)
	Cancel requests. The specified requests are canceled unless already being processed. However, cancelation cannot be guaranteed. Cancelled requests must still be waited for in order to ensure correct operation. More...

std::ostream &	stxxl::operator<< (std::ostream &out, const request &req)

template<class RequestIterator >
RequestIterator	stxxl::poll_any (RequestIterator reqs_begin, RequestIterator reqs_end)
	Polls requests. More...

bool	stxxl::poll_any (request_ptr req_array[], size_t count, size_t &index)
	Polls requests. More...

template<class RequestIterator >
void	stxxl::wait_all (RequestIterator reqs_begin, RequestIterator reqs_end)
	Collection of functions to track statuses of a number of requests. More...

void	stxxl::wait_all (request_ptr req_array[], size_t count)
	Suspends calling thread until all given requests are completed. More...

template<class RequestIterator >
RequestIterator	stxxl::wait_any (RequestIterator reqs_begin, RequestIterator reqs_end)
	Suspends calling thread until any of requests is completed. More...

size_t	stxxl::wait_any (request_ptr req_array[], size_t count)
	Suspends calling thread until any of requests is completed. More...

Detailed Description

Encapsulation of an I/O request, queues for requests and threads to process them.

Macro Definition Documentation

#define STXXL_BLOCK_ALIGN 4096

Definition at line 33 of file request.h.

Referenced by stxxl::request::check_alignment(), stxxl::mem_file::discard(), stxxl::fileperblock_file< base_file_type >::lock(), and stxxl::typed_block< RawSize, Type, NRef, MetaInfoType >::typed_block().

Typedef Documentation

typedef counting_ptr<request> stxxl::request_ptr

A reference counting pointer for request.

Definition at line 113 of file request.h.

Function Documentation

template<class RequestIterator >

std::iterator_traits<RequestIterator>::difference_type stxxl::cancel_all	(	RequestIterator	reqs_begin,
		RequestIterator	reqs_end
	)

Cancel requests. The specified requests are canceled unless already being processed. However, cancelation cannot be guaranteed. Cancelled requests must still be waited for in order to ensure correct operation.

Parameters

reqs_begin	begin of request sequence
reqs_end	end of request sequence

Returns: number of request canceled

Definition at line 58 of file request_operations.h.

std::ostream& stxxl::operator<<	(	std::ostream &	out,
		const request &	req
	)

inline

Definition at line 107 of file request.h.

References stxxl::request::print().

template<class RequestIterator >

RequestIterator stxxl::poll_any	(	RequestIterator	reqs_begin,
		RequestIterator	reqs_end
	)

Polls requests.

Parameters

reqs_begin	begin of request sequence to poll
reqs_end	end of request sequence to poll

Returns: true if any of requests is completed, then index contains valid value, otherwise false

Definition at line 75 of file request_operations.h.

Referenced by stxxl::poll_any().

bool stxxl::poll_any	(	request_ptr	req_array[],
		size_t	count,
		size_t &	index
	)

inline

Polls requests.

Parameters

req_array	array of request_ptr objects
count	size of req_array
index	contains index of the first completed request if any

Returns: true if any of requests is completed, then index contains valid value, otherwise false

Definition at line 92 of file request_operations.h.

References stxxl::count(), and stxxl::poll_any().

template<class RequestIterator >

void stxxl::wait_all	(	RequestIterator	reqs_begin,
		RequestIterator	reqs_end
	)

Collection of functions to track statuses of a number of requests.

Suspends calling thread until all given requests are completed.

Parameters

reqs_begin	begin of request sequence to wait for
reqs_end	end of request sequence to wait for

Definition at line 34 of file request_operations.h.

Referenced by stxxl::ksort_local::check_ksorted_runs(), stxxl::sort_local::check_sorted_runs(), stxxl::stream::check_sorted_runs(), stxxl::stream::basic_runs_creator< Input, CompareType, BlockSize, AllocStr >::compute_result(), stxxl::sort_local::create_runs(), stxxl::ksort_local::create_runs(), stxxl::ksort(), stxxl::normal_stack< StackConfig >::pop(), stxxl::grow_shrink_stack< StackConfig >::pop(), stxxl::normal_stack< StackConfig >::push(), stxxl::vector< ValueType >::read_page(), stxxl::stl_in_memory_sort(), stxxl::wait_all(), stxxl::vector< ValueType >::write_page(), and stxxl::grow_shrink_stack< StackConfig >::~grow_shrink_stack().

void stxxl::wait_all	(	request_ptr	req_array[],
		size_t	count
	)

inline

Suspends calling thread until all given requests are completed.

Parameters

req_array	array of request_ptr objects
count	size of req_array

Definition at line 43 of file request_operations.h.

References stxxl::wait_all().

template<class RequestIterator >

RequestIterator stxxl::wait_any	(	RequestIterator	reqs_begin,
		RequestIterator	reqs_end
	)

Suspends calling thread until any of requests is completed.

Parameters

reqs_begin	begin of request sequence to wait for
reqs_end	end of request sequence to wait for

Returns: index in req_array pointing to the first completed request

Definition at line 104 of file request_operations.h.

References stxxl::onoff_switch::wait_for_on().

Referenced by stxxl::buffered_writer< block_type >::get_free_block(), stxxl::write_pool< BlockType >::steal(), and stxxl::wait_any().

size_t stxxl::wait_any	(	request_ptr	req_array[],
		size_t	count
	)

inline

Suspends calling thread until any of requests is completed.

Parameters

req_array	array of `request_ptr` objects
count	size of req_array

Returns: index in req_array pointing to the first completed request

Definition at line 149 of file request_operations.h.

References stxxl::wait_any().

Classes

Macros

Typedefs

Functions

Detailed Description

Macro Definition Documentation

Typedef Documentation

Function Documentation