An implementation of managedSwap that is capable of kernel asynchronousIO. More...

#include <managedFileSwap.h>

Inheritance diagram for rambrain::managedFileSwap:

Public Member Functions
	managedFileSwap (global_bytesize size, const char *filemask, global_bytesize oneFile=0, bool enableDMA=false)

virtual	~managedFileSwap ()

virtual void	swapDelete (managedMemoryChunk *chunk)
	Mark chunk as deleted. More...

virtual global_bytesize	swapIn (managedMemoryChunk **chunklist, unsigned int nchunks)
	Trigger swap in of the chunks pointed to by chunklist. More...

virtual global_bytesize	swapIn (managedMemoryChunk *chunk)
	Trigger swap in of the chunk pointed to by chunk. More...

virtual global_bytesize	swapOut (managedMemoryChunk **chunklist, unsigned int nchunks)
	Trigger swap out of the chunks pointed to by chunklist. More...

virtual global_bytesize	swapOut (managedMemoryChunk *chunk)
	Trigger swap out of the chunk pointed to by chunk. More...

virtual bool	extendSwap (global_bytesize size)
	extend swap by size number of bytes More...

virtual bool	extendSwapByPolicy (global_bytesize min_size)
	extend swap by policy More...

void	setDMA (bool arg1)

virtual void	close ()
	Close the swap if not already closed. More...

Public Member Functions inherited from rambrain::managedSwap
	managedSwap (global_bytesize size)

virtual	~managedSwap ()

virtual global_bytesize	getSwapSize () const
	Simple getter. More...

virtual global_bytesize	getUsedSwap () const
	Simple getter. More...

virtual global_bytesize	getFreeSwap () const
	Simple getter. More...

virtual swapPolicy	getSwapPolicy () const

virtual swapPolicy	setSwapPolicy (swapPolicy newPolicy)

size_t	getMemoryAlignment () const
	Returns possible memory alignment restrictions. More...

void	claimUsageof (global_bytesize bytes, bool rambytes, bool used)
	account for memory usage change More...

void	waitForCleanExit ()
	Function waits for all asynchronous IO to complete. The wait is implemented non-performant as a normal user does not have to wait for this. Implementing this with a _cond just destroys performance in the respective swapIn/out procedures without increasing any user space functionality. More...

Public Attributes
const unsigned int	pageSize

Protected Member Functions
void	asyncIoArrived (rambrain::pageFileLocation ref, struct io_event aio)
	deals with a single asynchronous IO event completion More...

void	completeTransactionOn (rambrain::pageFileLocation *ref, bool lock=true)
	called to finish a transaction when all pending aio on a managedMemoryChunk has completed More...

virtual bool	checkForAIO ()
	gives this class the chance to treat incoming aio events More...

void	my_io_submit (struct iocb *aio)

bool	cleanupCachedElements (rambrain::global_bytesize minimum_size=0)
	throws out cached elements still in ram but also resident on disk. This makes space in situations of low swap memory More...

virtual void	invalidateCacheFor (managedMemoryChunk &chunk)
	tells managedFileSwap that the chunk under consideration might have been changed by user and needs to be copied out freshly More...

global_bytesize	getFreeDiskSpace ()
	returns free disk space at file system location specified by filemask More...

Static Protected Member Functions
static void	sigStat (int signum)
	returns some statistics. Typically, we will be sensitive to SIGUSR2 if compiled with -DSWAPSTATS=on More...

static void *	io_submit_worker (void *ptr)

static void *	io_arrrive_worker (void *ptr)

Protected Attributes
bool	deleteFilesOnExit = true

struct iocb	aio_template

io_context_t	aio_context = 0

unsigned int	aio_max_transactions = 10240

struct io_event *	aio_eventarr

pthread_mutex_t	aioWaiterLock = PTHREAD_MUTEX_INITIALIZER

std::unordered_map< struct iocb , pageFileLocation >	pendingAios

pthread_mutex_t	io_submit_lock = PTHREAD_MUTEX_INITIALIZER

pthread_cond_t	io_submit_cond = PTHREAD_COND_INITIALIZER

unsigned int	io_submit_num_threads = 1

pthread_t *	io_submit_threads

pthread_t	io_waiter_thread

pthread_t	io_arrive_thread

std::queue< struct iocb * >	io_submit_requests

bool	io_arrive_work = true

Protected Attributes inherited from rambrain::managedSwap
global_bytesize	swapSize

global_bytesize	swapUsed

global_bytesize	swapFree

unsigned int	totalSwapActionsQueued = 0

size_t	memoryAlignment = 1

swapPolicy	policy = swapPolicy::fixed

bool	closed = false

Static Protected Attributes
static managedFileSwap *	instance = NULL

Private Member Functions
pageFileLocation	determinePFLoc (global_offset g_offset, global_bytesize length) const
	generate a pageFileLocation object given a global offset and a length of the data. This maps our "virtual" adress space to physical locations in a certain file More...

global_offset	determineGlobalOffset (const pageFileLocation &ref) const
	maps from physical location to "virtual" adress More...

bool	openSwapFiles ()
	opens swap files according to settings More...

bool	openSwapFileRange (unsigned int start, unsigned int stop)
	opens certain range of swap files according to settings More...

void	closeSwapFiles ()
	closes swap files More...

void	scheduleCopy (rambrain::pageFileLocation &ref, void ramBuf, int tracker, bool reverse=false)
	Schedules an elementary pageFileLocation chunk for copying (in or out) More...

void	copyMem (rambrain::pageFileLocation &ref, void *ramBuf, bool reverse=false)
	Schedules copying on level of whole managedMemoryChunks and calls scheduleCopy on the assigned parts. More...

void	copyMem (void *ramBuf, rambrain::pageFileLocation &ref)
	Convenience function for reverse copying. More...

void	scheduleCopy (void ramBuf, pageFileLocation &ref, int parttracker)
	Convenience function for reverse scheduling a copy. More...

size_t	getMemoryAlignment () const
	If we have any restrictions regarding memory alignment of RAM buffers(DMA), this function tells us about it. More...

pageFileLocation *	pfmalloc (rambrain::global_bytesize size, rambrain::managedMemoryChunk *chunk)
	Tries to find space in the swapFiles to write out an object of size size and returns first pageFileLocation to it. More...

void	pffree (pageFileLocation *pagePtr)

pageFileLocation *	allocInFree (pageFileLocation *freeChunk, global_bytesize size)
	Helper function for pfmalloc. More...

Private Attributes
const char *	filemask

unsigned int	pageFileNumber

global_bytesize	pageFileSize

float	swapFileResizeFrac = .1

struct swapFileDesc *	swapFiles = NULL

std::map< global_offset, pageFileLocation * >	free_space

std::map< global_offset, pageFileLocation * >	all_space

bool	enableDMA = false

Friends
class	::managedFileSwap_Unit_SwapAllocation_Test

class	::managedFileSwap_Integration_RandomAccess_Test

class	::managedFileSwap_Integration_RandomAccessVariousSize_Test

class	::managedFileSwap_Unit_SwapPolicy_Test

Detailed Description

An implementation of managedSwap that is capable of kernel asynchronousIO.

Note: we also support DMA, however this is not recommended as kernel caching&buffering will be circumvent. For our use case this turns out to slow down things more and we do not make best use of system resources.; all public functions of managedFileSwap need to be called holding stateChangeMutex

Definition at line 107 of file managedFileSwap.h.

Constructor & Destructor Documentation

rambrain::managedFileSwap::managedFileSwap	(	global_bytesize	size,
		const char *	filemask,
		global_bytesize	oneFile = `0`,
		bool	enableDMA = `false`
	)

Definition at line 44 of file managedFileSwap.cpp.

rambrain::managedFileSwap::~managedFileSwap ( )

virtual

Definition at line 113 of file managedFileSwap.cpp.

Member Function Documentation

pageFileLocation * rambrain::managedFileSwap::allocInFree	(	pageFileLocation *	freeChunk,
		global_bytesize	size
	)

private

Helper function for pfmalloc.

Definition at line 399 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::asyncIoArrived	(	rambrain::pageFileLocation *	ref,
		struct io_event *	aio
	)

protected

deals with a single asynchronous IO event completion

Definition at line 828 of file managedFileSwap.cpp.

bool rambrain::managedFileSwap::checkForAIO ( )

protectedvirtual

gives this class the chance to treat incoming aio events

Returns: true if there is pending IO to wait for, false otherwise

Warning: if false is returned, immediate waiting for pending aio results in deadlock

Reimplemented from rambrain::managedSwap.

Definition at line 767 of file managedFileSwap.cpp.

bool rambrain::managedFileSwap::cleanupCachedElements ( rambrain::global_bytesize minimum_size = 0 )

protectedvirtual

throws out cached elements still in ram but also resident on disk. This makes space in situations of low swap memory

Reimplemented from rambrain::managedSwap.

Definition at line 924 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::close ( )

virtual

Close the swap if not already closed.

Note: Not automatically done by destructor

Warning: Swap can not be used anymore afterwards

Implements rambrain::managedSwap.

Definition at line 143 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::closeSwapFiles ( )

private

closes swap files

Definition at line 119 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::completeTransactionOn	(	rambrain::pageFileLocation *	ref,
		bool	lock = `true`
	)

protected

called to finish a transaction when all pending aio on a managedMemoryChunk has completed

Definition at line 708 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::copyMem	(	rambrain::pageFileLocation &	ref,
		void *	ramBuf,
		bool	reverse = `false`
	)

private

Schedules copying on level of whole managedMemoryChunks and calls scheduleCopy on the assigned parts.

Parameters

ref	the pageFileLocation the chunks data should be copied to
ramBuf	pointer to the managedMemoryChunk data buffer
reverse	copy in the other direction

Definition at line 865 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::copyMem	(	void *	ramBuf,
		rambrain::pageFileLocation &	ref
	)

inlineprivate

Convenience function for reverse copying.

Definition at line 161 of file managedFileSwap.h.

global_offset rambrain::managedFileSwap::determineGlobalOffset ( const pageFileLocation & ref ) const

inlineprivate

maps from physical location to "virtual" adress

Definition at line 604 of file managedFileSwap.cpp.

pageFileLocation rambrain::managedFileSwap::determinePFLoc	(	global_offset	g_offset,
		global_bytesize	length
	)		const

private

generate a pageFileLocation object given a global offset and a length of the data. This maps our "virtual" adress space to physical locations in a certain file

Definition at line 608 of file managedFileSwap.cpp.

bool rambrain::managedFileSwap::extendSwap ( global_bytesize size )

virtual

extend swap by size number of bytes

Returns: success

Reimplemented from rambrain::managedSwap.

Definition at line 262 of file managedFileSwap.cpp.

bool rambrain::managedFileSwap::extendSwapByPolicy ( global_bytesize min_size )

virtual

extend swap by policy

Returns: success

Parameters

min_size Minimum size the swap has to be extended before success is returned

Reimplemented from rambrain::managedSwap.

Definition at line 207 of file managedFileSwap.cpp.

global_bytesize rambrain::managedFileSwap::getFreeDiskSpace ( )

protected

returns free disk space at file system location specified by filemask

Definition at line 289 of file managedFileSwap.cpp.

size_t rambrain::managedFileSwap::getMemoryAlignment ( ) const

inlineprivate

If we have any restrictions regarding memory alignment of RAM buffers(DMA), this function tells us about it.

Definition at line 170 of file managedFileSwap.h.

void rambrain::managedFileSwap::invalidateCacheFor ( managedMemoryChunk & chunk )

protectedvirtual

tells managedFileSwap that the chunk under consideration might have been changed by user and needs to be copied out freshly

Reimplemented from rambrain::managedSwap.

Definition at line 947 of file managedFileSwap.cpp.

void * rambrain::managedFileSwap::io_arrrive_worker ( void * ptr )

staticprotected

Definition at line 682 of file managedFileSwap.cpp.

void * rambrain::managedFileSwap::io_submit_worker ( void * ptr )

staticprotected

Definition at line 655 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::my_io_submit ( struct iocb * aio )

protected

Definition at line 699 of file managedFileSwap.cpp.

bool rambrain::managedFileSwap::openSwapFileRange	(	unsigned int	start,
		unsigned int	stop
	)

private

opens certain range of swap files according to settings

Definition at line 171 of file managedFileSwap.cpp.

bool rambrain::managedFileSwap::openSwapFiles ( )

private

opens swap files according to settings

Definition at line 192 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::pffree ( pageFileLocation * pagePtr )

private

Definition at line 434 of file managedFileSwap.cpp.

pageFileLocation * rambrain::managedFileSwap::pfmalloc	(	rambrain::global_bytesize	size,
		rambrain::managedMemoryChunk *	chunk
	)

private

Tries to find space in the swapFiles to write out an object of size size and returns first pageFileLocation to it.

Priority: -Use first free chunk that fits completely -Distribute over free locations -look for read-in memory that can be overwritten -delete cached files and look again

Definition at line 306 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::scheduleCopy	(	rambrain::pageFileLocation &	ref,
		void *	ramBuf,
		int *	tracker,
		bool	reverse = `false`
	)

private

Schedules an elementary pageFileLocation chunk for copying (in or out)

Definition at line 617 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::scheduleCopy	(	void *	ramBuf,
		pageFileLocation &	ref,
		int *	parttracker
	)

inlineprivate

Convenience function for reverse scheduling a copy.

Definition at line 165 of file managedFileSwap.h.

void rambrain::managedFileSwap::setDMA ( bool arg1 )

Definition at line 137 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::sigStat ( int signum )

staticprotected

returns some statistics. Typically, we will be sensitive to SIGUSR2 if compiled with -DSWAPSTATS=on

Definition at line 890 of file managedFileSwap.cpp.

void rambrain::managedFileSwap::swapDelete ( managedMemoryChunk * chunk )

virtual

Mark chunk as deleted.

Note: this is only called when deleting a chunk in managedMemory if chunk->swapBuf is not NULL; this function must be called having stateChangeMutex acquired.

Implements rambrain::managedSwap.

Definition at line 504 of file managedFileSwap.cpp.

global_bytesize rambrain::managedFileSwap::swapIn	(	managedMemoryChunk **	chunklist,
		unsigned int	nchunks
	)

virtual

Trigger swap in of the chunks pointed to by chunklist.

Note: this function must be called having stateChangeMutex acquired.

Implements rambrain::managedSwap.

Definition at line 539 of file managedFileSwap.cpp.

global_bytesize rambrain::managedFileSwap::swapIn ( managedMemoryChunk * chunk )

virtual

Trigger swap in of the chunk pointed to by chunk.

Note: this function must be called having stateChangeMutex acquired.

Implements rambrain::managedSwap.

Definition at line 516 of file managedFileSwap.cpp.

global_bytesize rambrain::managedFileSwap::swapOut	(	managedMemoryChunk **	chunklist,
		unsigned int	nchunks
	)

virtual

Trigger swap out of the chunks pointed to by chunklist.

Note: this function must be called having stateChangeMutex acquired.

Implements rambrain::managedSwap.

Definition at line 594 of file managedFileSwap.cpp.

global_bytesize rambrain::managedFileSwap::swapOut ( managedMemoryChunk * chunk )

virtual

Trigger swap out of the chunk pointed to by chunk.

Note: this function must be called having stateChangeMutex acquired.

Implements rambrain::managedSwap.

Definition at line 548 of file managedFileSwap.cpp.

Friends And Related Function Documentation

friend class ::managedFileSwap_Integration_RandomAccess_Test

friend

Definition at line 241 of file managedFileSwap.h.

friend class ::managedFileSwap_Integration_RandomAccessVariousSize_Test

friend

Definition at line 242 of file managedFileSwap.h.

friend class ::managedFileSwap_Unit_SwapAllocation_Test

friend

Definition at line 240 of file managedFileSwap.h.

friend class ::managedFileSwap_Unit_SwapPolicy_Test

friend

Definition at line 243 of file managedFileSwap.h.

Member Data Documentation

io_context_t rambrain::managedFileSwap::aio_context = 0

protected

Definition at line 203 of file managedFileSwap.h.

struct io_event* rambrain::managedFileSwap::aio_eventarr

protected

Definition at line 205 of file managedFileSwap.h.

unsigned int rambrain::managedFileSwap::aio_max_transactions = 10240

protected

Definition at line 204 of file managedFileSwap.h.

struct iocb rambrain::managedFileSwap::aio_template

protected

Definition at line 202 of file managedFileSwap.h.

pthread_mutex_t rambrain::managedFileSwap::aioWaiterLock = PTHREAD_MUTEX_INITIALIZER

protected

Definition at line 206 of file managedFileSwap.h.

std::map<global_offset, pageFileLocation *> rambrain::managedFileSwap::all_space

private

Definition at line 183 of file managedFileSwap.h.

bool rambrain::managedFileSwap::deleteFilesOnExit = true

protected

Definition at line 188 of file managedFileSwap.h.

bool rambrain::managedFileSwap::enableDMA = false

private

Definition at line 186 of file managedFileSwap.h.

const char* rambrain::managedFileSwap::filemask

private

Definition at line 141 of file managedFileSwap.h.

std::map<global_offset, pageFileLocation *> rambrain::managedFileSwap::free_space

private

Definition at line 182 of file managedFileSwap.h.

managedFileSwap * rambrain::managedFileSwap::instance = NULL

staticprotected

Definition at line 210 of file managedFileSwap.h.

pthread_t rambrain::managedFileSwap::io_arrive_thread

protected

Definition at line 220 of file managedFileSwap.h.

bool rambrain::managedFileSwap::io_arrive_work = true

protected

Definition at line 228 of file managedFileSwap.h.

pthread_cond_t rambrain::managedFileSwap::io_submit_cond = PTHREAD_COND_INITIALIZER

protected

Definition at line 216 of file managedFileSwap.h.

pthread_mutex_t rambrain::managedFileSwap::io_submit_lock = PTHREAD_MUTEX_INITIALIZER

protected

Definition at line 215 of file managedFileSwap.h.

unsigned int rambrain::managedFileSwap::io_submit_num_threads = 1

protected

Definition at line 217 of file managedFileSwap.h.

std::queue<struct iocb *> rambrain::managedFileSwap::io_submit_requests

protected

Definition at line 222 of file managedFileSwap.h.

pthread_t* rambrain::managedFileSwap::io_submit_threads

protected

Definition at line 218 of file managedFileSwap.h.

pthread_t rambrain::managedFileSwap::io_waiter_thread

protected

Definition at line 219 of file managedFileSwap.h.

unsigned int rambrain::managedFileSwap::pageFileNumber

private

Definition at line 143 of file managedFileSwap.h.

global_bytesize rambrain::managedFileSwap::pageFileSize

private

Definition at line 144 of file managedFileSwap.h.

const unsigned int rambrain::managedFileSwap::pageSize

Definition at line 126 of file managedFileSwap.h.

std::unordered_map<struct iocb *, pageFileLocation *> rambrain::managedFileSwap::pendingAios

protected

Definition at line 208 of file managedFileSwap.h.

float rambrain::managedFileSwap::swapFileResizeFrac = .1

private

Definition at line 147 of file managedFileSwap.h.

struct swapFileDesc* rambrain::managedFileSwap::swapFiles = NULL

private

Definition at line 149 of file managedFileSwap.h.

The documentation for this class was generated from the following files:

/home/rambrainbuild/docubrain/src/managedFileSwap.h
/home/rambrainbuild/docubrain/src/managedFileSwap.cpp

Public Member Functions

Public Attributes

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Static Protected Attributes

Private Member Functions

Private Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation