wrench::SimpleStorageService Class Reference

A storage service that provides direct access to some storage resources (e.g., one or more disks). An important (configurable) property of the storage service is SimpleStorageServiceProperty::BUFFER_SIZE (see documentation thereof), which defines the buffer size that the storage service uses. Specifically, when the storage service receives/sends data from/to the network, it does so in a loop over data "chunks", with pipelined network and disk I/O operations. The smaller the buffer size the more "fluid" the model, but the more time-consuming the simulation. A large buffer size, however, may lead to less realistic simulations. At the extreme, an infinite buffer size would correspond to fully sequential executions (first a network receive/send, and then a disk write/read). Setting the buffer size to "0" corresponds to a fully fluid model in which individual data chunk operations are not simulated, thus achieving both accuracy (unless one specifically wishes to study the effects of buffering) and quick simulation times. For now, setting the buffer size to "0" is not implemented. The default buffer size is 10 MiB (note that the user can always declare a disk with arbitrary bandwidth in the platform description XML). More...

#include <SimpleStorageService.h>

Inheritance diagram for wrench::SimpleStorageService:

Public Member Functions
	SimpleStorageService (std::string hostname, std::set< std::string > mount_points, WRENCH_PROPERTY_COLLECTION_TYPE property_list={}, WRENCH_MESSAGE_PAYLOADCOLLECTION_TYPE messagepayload_list={})
	Public constructor. More...
Public Member Functions inherited from wrench::StorageService
virtual std::map< std::string, double >	getFreeSpace ()
	Synchronously asks the storage service for its capacity at all its mount points. More...
std::string	getMountPoint ()
	Get the mount point (will throw is more than one) More...
std::set< std::string >	getMountPoints ()
	Get the set of mount points. More...
virtual std::map< std::string, double >	getTotalSpace ()
	Get the total static capacity of the storage service (in zero simulation time) More...
bool	hasMountPoint (std::string mp)
	Checked whether the storage service has a particular mount point. More...
bool	hasMultipleMountPoints ()
	Checked whether the storage service has multiple mount points. More...
void	stop () override
	Stop the service.
Public Member Functions inherited from wrench::Service
void	assertServiceIsUp ()
	Throws an exception if the service is not up. More...
std::string	getHostname ()
	Get the name of the host on which the service is / will be running. More...
double	getNetworkTimeoutValue ()
	Returns the service's network timeout value. More...
std::string	getPhysicalHostname ()
	Get the physical name of the host on which the service is / will be running. More...
bool	getPropertyValueAsBoolean (WRENCH_PROPERTY_TYPE)
	Get a property of the Service as a boolean. More...
double	getPropertyValueAsDouble (WRENCH_PROPERTY_TYPE)
	Get a property of the Service as a double. More...
std::string	getPropertyValueAsString (WRENCH_PROPERTY_TYPE)
	Get a property of the Service as a string. More...
unsigned long	getPropertyValueAsUnsignedLong (WRENCH_PROPERTY_TYPE)
	Get a property of the Service as an unsigned long. More...
bool	isUp ()
	Returns true if the service is UP, false otherwise. More...
void	resume ()
	Resume the service. More...
void	setNetworkTimeoutValue (double value)
	Sets the service's network timeout value. More...
void	start (std::shared_ptr< Service > this_service, bool daemonize, bool auto_restart)
	Start the service. More...
void	suspend ()
	Suspend the service.

Additional Inherited Members
Static Public Member Functions inherited from wrench::StorageService
static void	createFile (std::shared_ptr< DataFile >file, std::shared_ptr< FileLocation > location)
	Store a file at a particular mount point ex nihilo (this instantly creates the file at the storage service - zero simulation time). Will do nothing (and won't complain) if the file already exists at that location. More...
static void	deleteFile (std::shared_ptr< DataFile >file, std::shared_ptr< FileLocation > location, std::shared_ptr< FileRegistryService > file_registry_service=nullptr)
	Synchronously delete a file at a location. More...
static bool	lookupFile (std::shared_ptr< DataFile >file, std::shared_ptr< FileLocation > location)
	Synchronously asks the storage service whether it holds a file. More...
static void	readFile (std::shared_ptr< DataFile >file, std::shared_ptr< FileLocation > location)
	Synchronously read a file from the storage service. More...
static void	readFile (std::shared_ptr< DataFile >file, std::shared_ptr< FileLocation > location, double num_bytes)
	Synchronously read a file from the storage service. More...
static void	writeFile (std::shared_ptr< DataFile >file, std::shared_ptr< FileLocation > location)
	Synchronously write a file to the storage service. More...

Detailed Description

A storage service that provides direct access to some storage resources (e.g., one or more disks). An important (configurable) property of the storage service is SimpleStorageServiceProperty::BUFFER_SIZE (see documentation thereof), which defines the buffer size that the storage service uses. Specifically, when the storage service receives/sends data from/to the network, it does so in a loop over data "chunks", with pipelined network and disk I/O operations. The smaller the buffer size the more "fluid" the model, but the more time-consuming the simulation. A large buffer size, however, may lead to less realistic simulations. At the extreme, an infinite buffer size would correspond to fully sequential executions (first a network receive/send, and then a disk write/read). Setting the buffer size to "0" corresponds to a fully fluid model in which individual data chunk operations are not simulated, thus achieving both accuracy (unless one specifically wishes to study the effects of buffering) and quick simulation times. For now, setting the buffer size to "0" is not implemented. The default buffer size is 10 MiB (note that the user can always declare a disk with arbitrary bandwidth in the platform description XML).

Constructor & Destructor Documentation

SimpleStorageService()

wrench::SimpleStorageService::SimpleStorageService	(	std::string	hostname,
		std::set< std::string >	mount_points,
		WRENCH_PROPERTY_COLLECTION_TYPE	property_list = {},
		WRENCH_MESSAGE_PAYLOADCOLLECTION_TYPE	messagepayload_list = {}
	)

Public constructor.

Parameters

hostname	the name of the host on which to start the service
mount_points	the set of mount points
property_list	a property list ({} means "use all defaults")
messagepayload_list	a message payload list ({} means "use all defaults")

---

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

• SimpleStorageService.h
• SimpleStorageService.cpp