wrench::SimpleStorageService

class SimpleStorageService : public wrench::StorageService

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).

Public Functions

SimpleStorageService(const 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”)

~SimpleStorageService() override

Destructor.

virtual void cleanup(bool has_returned_from_main, int return_value) override

Cleanup method.

Parameters

  • has_returned_from_main – whether main() returned

  • return_value – the return value (if main() returned)

double countRunningFileTransferThreads()

Get number of File Transfer Threads that are currently running or are pending.

Returns

The number of threads

virtual double getLoad() override

Get the load (number of concurrent reads) on the storage service.

Returns

the load on the service