wrench::XRootD::Node

class Node : public wrench::StorageService

An XRootD node, this can be either a supervisor or a storage server. All nodes are classified as storage services even though not all have physical storage Unless a node is also has an internal storage service, some normal storage service messages will error out. Only File Read, locate, and delete are supported at this time, anything else requires talking directly to a specific file server with physical storage. Nodes not directly be created, instead an XRootD Metavisor should create them.

Public Functions

Node(Deployment *deployment, const std::string &hostname, WRENCH_PROPERTY_COLLECTION_TYPE storage_property_list, WRENCH_MESSAGE_PAYLOADCOLLECTION_TYPE storage_messagepayload_list)

Constructor, should not be used directly except by XRootD createNode.

Parameters:

deployment – the XRootD deployment this node belongs to
hostname – the name of the host on which the service and its storage service should run
property_list – A property list
messagepayload_list – A Message Payload list

std::shared_ptr<Node> addChildStorageServer(const std::string &hostname, const std::string &mount_point, WRENCH_PROPERTY_COLLECTION_TYPE storage_property_list = {}, WRENCH_MESSAGE_PAYLOADCOLLECTION_TYPE storage_messagepayload_list = {}, WRENCH_PROPERTY_COLLECTION_TYPE node_property_list = {}, WRENCH_MESSAGE_PAYLOADCOLLECTION_TYPE node_messagepayload_list = {})

Adds a child, which will be a storage server, to a node.

Parameters:

hostname – the name of the host on which the child will run
mount_point – the mount point at that host
storage_property_list – the storage server’s property list
storage_messagepayload_list – the storage server’s message payload list
node_property_list – the XRootD node’s property list
node_messagepayload_list – the XRootD node’s message payload list

Returns:

The child

std::shared_ptr<Node> addChildSupervisor(const std::string &hostname)

Adds a child, which will be a supervisor, to a node.

Parameters:: hostname – the name of the host on which the child will run
Returns:: The child

bool cached(shared_ptr<DataFile> file)

Check the cache for a file.

Parameters:: file – The file to check the cache for
Returns:: true if the file is cached, false otherwise

inline void createFile(const std::shared_ptr<DataFile> &file)

Create a file at the storage service (in zero simulated time)

Parameters:: file – a file

inline void createFile(const std::shared_ptr<DataFile> &file, const std::string &path)

Create a file at the storage service (in zero simulated time)

Parameters:

file – a file
path – a path

virtual void createFile(const std::shared_ptr<FileLocation> &location) override

create a new file in the federation on this node. Use instead of wrench::Simulation::createFile when adding files to XRootD

Parameters:: location – a file location, must be the same object as the function is invoked on
Throws:: std::invalid_argument –

void createFile(const std::shared_ptr<FileLocation> &location) = 0

Create a file at the storage service (in zero simulated time)

Parameters:: location – a location

inline void deleteFile(const std::shared_ptr<DataFile> &file)

Delete a file at the storage service (incurs simulated overheads)

Parameters:: file – a file

inline void deleteFile(const std::shared_ptr<DataFile> &file, const std::string &path)

Delete a file at the storage service (incurs simulated overheads)

Parameters:

file – a file
path – a path

inline void deleteFile(const std::shared_ptr<FileLocation> &location)

Delete a file at the storage service (incurs simulated overheads)

Parameters:: location – a location

void deleteFile(S4U_CommPort *answer_commport, const std::shared_ptr<FileLocation> &location, bool wait_for_answer)

Delete a file on the storage service.

Parameters:

answer_commport – the answer commport to which the reply from the server should be sent
location – the location to delete
wait_for_answer – whether this call should

virtual double getBufferSize() const override

Determine the storage service’s buffer size.

Returns:: a size in bytes

std::set<std::shared_ptr<FileLocation>> getCached(shared_ptr<DataFile> file)

Get all cached locations of the file.

Parameters:: file – The file to check the cache for
Returns:: A set of valid cached files. Empty set if none are cached

std::shared_ptr<Node> getChild(unsigned int n)

A meta tree traversal operation to get the nth child of this node.

Parameters:: n – The index of the child to receive. Nodes are in order added
Returns:: the Child Nodes shared pointer, or nullptr if this node is a leaf

virtual double getFileLastWriteDate(const std::shared_ptr<FileLocation> &location) override

Get a file’s last write date at a location (in zero simulated time)

Parameters:: location – the file location
Returns:: the file’s last write date, or -1 if the file is not found

virtual double getLoad() override

Get the load of the underlying storage service.

Returns:: the load on the service

Node *getParent()

A Meta tree traversal to get the parent of this node.

Returns:: pointer supervisor. Will be nullptr if root

std::shared_ptr<SimpleStorageService> getStorageServer()

Gets the underlying storage server.

Returns:: A pointer to the simple storage server for this file server

virtual double getTotalSpace() override

Get the storage service’s total space (in zero simulated time)

Returns:: a capacity in bytes

inline bool hasFile(const std::shared_ptr<DataFile> &file)

Determines whether a file is present at the storage service (in zero simulated time)

Parameters:: file – a file
Returns:: true if the file is present, false otherwise

inline bool hasFile(const std::shared_ptr<DataFile> &file, const std::string &path)

Determines whether a file is present at the storage service (in zero simulated time)

Parameters:

file – a file
path – a path

Returns:

true if the file is present, false otherwise

virtual bool hasFile(const std::shared_ptr<FileLocation> &location) override

Determines whether the storage service has the file. This doesn’t simulate anything and is merely a zero-simulated-time data structure lookup. If you want to simulate the overhead of querying the StorageService, instead use lookupFile().

Parameters:: location – a location
Returns:: true if the file is present, false otherwise

bool hasFile(const std::shared_ptr<FileLocation> &location) = 0

Determines whether a file is present at the storage service (in zero simulated time)

Parameters:: location – a location
Returns:: true if the file is present, false otherwise

virtual bool isBufferized() const override

Determine whether the storage service is bufferized.

Returns:: true if bufferized, false otherwise

inline bool lookupFile(const std::shared_ptr<DataFile> &file)

Lookup whether a file exists on the storage service (incurs simulated overheads)

Parameters:: file – a file
Returns:: true if the file is present, or false

inline bool lookupFile(const std::shared_ptr<DataFile> &file, const std::string &path)

Lookup whether a file exists on the storage service (incurs simulated overheads)

Parameters:

file – a file
path – a path

Returns:

true if the file is present, or false

inline bool lookupFile(const std::shared_ptr<FileLocation> &location)

Lookup whether a file exists at a location on the storage service (incurs simulated overheads)

Parameters:: location – a location
Returns:: true if the file is present, or false

bool lookupFile(S4U_CommPort *answer_commport, const std::shared_ptr<FileLocation> &location)

Asks the storage service whether it holds a file.

Parameters:

answer_commport – the answer commport to which the reply from the server should be sent
location – the location to lookup

Returns:

true if the file is present, false otherwise

virtual int main() override

Main method of the daemon.

Returns:: 0 on termination

bool processNextMessage()

Process a received control message.

Returns:: false if the daemon should terminate

inline void readFile(const std::shared_ptr<DataFile> &file)