beehive.server

Class HashtableServerImpl

java.lang.Object

java.rmi.server.RemoteObject

java.rmi.server.RemoteServer

java.rmi.server.UnicastRemoteObject

beehive.server.HashtableServerImpl

All Implemented Interfaces:

HashtableServer, java.io.Serializable, java.rmi.Remote

public class HashtableServerImpl
extends java.rmi.server.UnicastRemoteObject
implements HashtableServer

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
float	CACHE_CLEANUP_TARGET
int	CACHE_TABLE_SIZE
int	CACHE_WINDOW
int	cacheInvalidationScheme
java.util.concurrent.ConcurrentHashMap<java.lang.String,java.lang.Object>	cacheTable
int	changeMasterCount
java.util.concurrent.ConcurrentHashMap<java.lang.String,NodeMetadata>	metaDataTable
int	myId
int	numServers
boolean	recordStats
java.util.concurrent.ConcurrentHashMap<java.lang.Integer,HashtableServer>	servers
boolean	useCaching

Constructor Summary

Constructors

Constructor and Description
HashtableServerImpl(java.lang.String url) server-id unaware contructor
HashtableServerImpl(java.lang.String url, int serverId) server-id aware contructor
HashtableServerImpl(java.lang.String url, int serverId, Config configParams) Constructor for the caching case

Method Summary

Modifier and Type	Method and Description
Node	cacheEvict(java.lang.String nodeId) cache eviction thread invokes this method when removing a copy from the cache table (cache replacement)
void	cacheEvictMasterNotify(java.lang.String cachingServerId, java.util.Hashtable<java.lang.String,java.lang.Long> evictedNodes) cache eviction thread invokes this method on the master site informing it of the cache eviction
void	cacheInvalidate(java.lang.String nodeId) Master server invokes this function on a remote server when asking it to invalidate its cache copy
java.util.Vector<ResultObject>	cachePut(java.util.Map<java.lang.Integer,java.util.Vector<Node>> nodes, long storageSystemThreadId) Bulk call for cachePut
ResultObject	cachePut(java.lang.String nodeId, Node node, int masterCopySite, long storageSystemThreadId) Once a node has been fetched for caching, insert into cache table.
void	clearStatContainers() Clear stat containers
void	configureServer(java.util.Vector<java.lang.String> hostList) Configure server to hold rmi handles of other servers Allows for inter-server communication
boolean	contains(java.lang.String key) Check if the table contains a given key
void	enableStats() Turn on stat recording
ResultObject	exec(NodeData n)
java.util.Vector<ResultObject>	execBulk(java.util.Vector<NodeData> keyList)
ResultObject	get(java.lang.String key, long storageSystemThreadId) Given a node id, returns a node to the storage system (application) Forks off to getUseCache in the useCaching = true case
java.util.Vector<java.lang.String>	getAllKeys() Get all node ids present in the main table (does not include cache table)
java.util.Vector<Node>	getAllNodes() Get all nodes present in the main table (does not include cache table)
java.util.Vector<Node>	getCachedObjects(java.util.Vector<java.lang.String> nodeIds)
ClusterMeasures	getClusterMeasures()
java.util.Vector<ResultObject>	getLocalNodes(java.util.Vector<java.lang.String> nodeIds, long storageSystemThreadId) Storage system invokes this method on the server when requesting nodes and status for those nodes which are not available Only used in caching case
Node	getNodeForCaching(java.lang.String nodeId, int cachingSite) Remote server invokes this method on the master site when requesting a cache copy
Node	getNodeFromCacheTable(java.lang.String nodeId) get node for nodeId from the cache table returns null if node not found
Node	getNodeFromTable(java.lang.String nodeId) get a node from the table
ResultObject	getNodeProperties(NodeData n) retrieve the node data for a node, given its node ids and the required properties
java.util.Vector<Node>	getNodesForCaching(java.util.Vector<java.lang.String> nodeIds, int cachingSite) Bulk call for getNodeForCaching
int	getNumServers()
java.util.Vector<ResultObject>	getObjects(java.util.Vector<java.lang.String> keyList) getObjects from the hash table.
java.util.Vector<ResultObject>	getObjectsProperties(java.util.Vector<NodeData> keyList) Bulk call to get object properties for a set of nodes
int	getServerId()
java.lang.String	getStats() Get the stats, called after program run terminates
void	loadNodes(java.util.Vector<Node> nodes) To load initial nodes into the table, used by the file loader
void	locationChange(int nodeId, java.lang.String servername) Inform the homesite that a node has been relocated.
ResultObject	lock(int nodeId) Lock an object to prevent its relocation
static void	main(java.lang.String[] args)
java.util.Date	ping() Test if the hashtable server is up
ResultObject	put(java.lang.String key, java.lang.Object value) put the node into the table, given a node-id Forks off to putUseCache in the useCaching = true case
ResultObject	put(java.lang.String key, java.lang.Object value, int callerServerId) put for the write through cache case
java.util.Vector<ResultObject>	putObjects(java.util.concurrent.ConcurrentHashMap<java.lang.String,Node> objList) putObjects back into the hash table
java.util.Vector<ResultObject>	putObjects(java.util.concurrent.ConcurrentHashMap<java.lang.String,Node> objList, int callingServerId) put objects back into the hash table for the write through cache case
ResultObject	putUseCache(java.lang.String key, java.lang.Object value, int callingServerId) putUseCache for the write through cache case also takes in a calling server id, to keep track of cache invaldations (write through cache = no invalidation on calling server)
ResultObject	relocate(int nodeId, java.lang.String serverName) called on the homesite when relocating a node to a remote server homesite makes a note of it in the location table
void	removeLocationTableEntry(java.lang.String key) Remove a key from the location table
void	setNumServers(int n)
ResultObject	updateNodeProperties(NodeData value) update the properties of a node, given the node id and the updated property map
java.util.Vector<ResultObject>	updateNodePropertiesParallel(java.util.Vector<NodeData> objList) This is the reflection counterpart of putObjects, used for bulk update of node properties repeatedly calls the updateNodeProperties (can be done in parallel)
void	writeThroughToCache(java.lang.String paramString, java.lang.Object value) write through to local cache, so that master does need to invalidate the copy on put
void	writeThroughToCacheBulk(java.util.concurrent.ConcurrentHashMap<java.lang.String,Node> map) bulk call for writeThroughToCache

Methods inherited from class java.rmi.server.UnicastRemoteObject

clone, exportObject, exportObject, exportObject, unexportObject

Methods inherited from class java.rmi.server.RemoteServer

getClientHost, getLog, setLog

Methods inherited from class java.rmi.server.RemoteObject

equals, getRef, hashCode, toString, toStub

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

myId

public int myId

cacheTable

public java.util.concurrent.ConcurrentHashMap<java.lang.String,java.lang.Object> cacheTable

metaDataTable

public java.util.concurrent.ConcurrentHashMap<java.lang.String,NodeMetadata> metaDataTable

changeMasterCount

public int changeMasterCount

useCaching

public boolean useCaching

recordStats

public boolean recordStats

cacheInvalidationScheme

public int cacheInvalidationScheme

CACHE_TABLE_SIZE

public int CACHE_TABLE_SIZE

CACHE_WINDOW

public int CACHE_WINDOW

CACHE_CLEANUP_TARGET

public float CACHE_CLEANUP_TARGET

numServers

public int numServers

servers

public java.util.concurrent.ConcurrentHashMap<java.lang.Integer,HashtableServer> servers

Constructor Detail

HashtableServerImpl

public HashtableServerImpl(java.lang.String url)
                    throws java.rmi.RemoteException

server-id unaware contructor

Parameters:

url -

Throws:

java.rmi.RemoteException

HashtableServerImpl

public HashtableServerImpl(java.lang.String url,
                           int serverId)
                    throws java.rmi.RemoteException

server-id aware contructor

Parameters:

url -

serverId -

Throws:

java.rmi.RemoteException

HashtableServerImpl

public HashtableServerImpl(java.lang.String url,
                           int serverId,
                           Config configParams)
                    throws java.rmi.RemoteException

Constructor for the caching case

Parameters:

url -

serverId -

configParams -

Throws:

java.rmi.RemoteException

Method Detail

configureServer

public void configureServer(java.util.Vector<java.lang.String> hostList)

Configure server to hold rmi handles of other servers Allows for inter-server communication

Parameters:

hostList -

enableStats

public void enableStats()

Turn on stat recording

ping

public java.util.Date ping()

Test if the hashtable server is up

Specified by:

ping in interface HashtableServer

Returns:

get

public ResultObject get(java.lang.String key,
                        long storageSystemThreadId)

Given a node id, returns a node to the storage system (application) Forks off to getUseCache in the useCaching = true case

Specified by:

get in interface HashtableServer

Parameters:

key -

storageSystemThreadId -

Returns:

put

public ResultObject put(java.lang.String key,
                        java.lang.Object value)
                 throws java.rmi.RemoteException

put the node into the table, given a node-id Forks off to putUseCache in the useCaching = true case

Specified by:

put in interface HashtableServer

Parameters:

key -

value -

Returns:

Throws:

java.rmi.RemoteException

put

public ResultObject put(java.lang.String key,
                        java.lang.Object value,
                        int callerServerId)
                 throws java.rmi.RemoteException

put for the write through cache case

Specified by:

put in interface HashtableServer

Parameters:

key -

value -

callerServerId -

Returns:

Throws:

java.rmi.RemoteException

putUseCache

public ResultObject putUseCache(java.lang.String key,
                                java.lang.Object value,
                                int callingServerId)
                         throws java.rmi.RemoteException

putUseCache for the write through cache case also takes in a calling server id, to keep track of cache invaldations (write through cache = no invalidation on calling server)

Parameters:

key -

value -

callingServerId -

Returns:

Throws:

java.rmi.RemoteException

getNodeProperties

public ResultObject getNodeProperties(NodeData n)
                               throws java.rmi.RemoteException

retrieve the node data for a node, given its node ids and the required properties

Specified by:

getNodeProperties in interface HashtableServer

Parameters:

n -

Returns:

Throws:

java.rmi.RemoteException

updateNodeProperties

public ResultObject updateNodeProperties(NodeData value)
                                  throws java.rmi.RemoteException

update the properties of a node, given the node id and the updated property map

Specified by:

updateNodeProperties in interface HashtableServer

Parameters:

value -

Returns:

Throws:

java.rmi.RemoteException

exec

public ResultObject exec(NodeData n)
                  throws java.rmi.RemoteException

Specified by:

exec in interface HashtableServer

Throws:

java.rmi.RemoteException

execBulk

public java.util.Vector<ResultObject> execBulk(java.util.Vector<NodeData> keyList)
                                        throws java.rmi.RemoteException

Specified by:

execBulk in interface HashtableServer

Throws:

java.rmi.RemoteException

getObjects

public java.util.Vector<ResultObject> getObjects(java.util.Vector<java.lang.String> keyList)

getObjects from the hash table. Called only in non-caching case

Specified by:

getObjects in interface HashtableServer

Parameters:

keyList -

Returns:

putObjects

public java.util.Vector<ResultObject> putObjects(java.util.concurrent.ConcurrentHashMap<java.lang.String,Node> objList)
                                          throws java.rmi.RemoteException

putObjects back into the hash table

Specified by:

putObjects in interface HashtableServer

Parameters:

objList -

Returns:

Throws:

java.rmi.RemoteException

putObjects

public java.util.Vector<ResultObject> putObjects(java.util.concurrent.ConcurrentHashMap<java.lang.String,Node> objList,
                                                 int callingServerId)
                                          throws java.rmi.RemoteException

put objects back into the hash table for the write through cache case

Specified by:

putObjects in interface HashtableServer

Parameters:

objList -

callingServerId -

Returns:

Throws:

java.rmi.RemoteException

getObjectsProperties

public java.util.Vector<ResultObject> getObjectsProperties(java.util.Vector<NodeData> keyList)
                                                    throws java.rmi.RemoteException

Bulk call to get object properties for a set of nodes

Specified by:

getObjectsProperties in interface HashtableServer

Parameters:

keyList -

Returns:

Throws:

java.rmi.RemoteException

getCachedObjects

public java.util.Vector<Node> getCachedObjects(java.util.Vector<java.lang.String> nodeIds)
                                        throws java.rmi.RemoteException

Specified by:

getCachedObjects in interface HashtableServer

Throws:

java.rmi.RemoteException

updateNodePropertiesParallel

public java.util.Vector<ResultObject> updateNodePropertiesParallel(java.util.Vector<NodeData> objList)
                                                            throws java.rmi.RemoteException

This is the reflection counterpart of putObjects, used for bulk update of node properties repeatedly calls the updateNodeProperties (can be done in parallel)

Specified by:

updateNodePropertiesParallel in interface HashtableServer

Parameters:

objList - - hashtable of nodeId/Node data object

Returns:

result obects for reflection

Throws:

java.rmi.RemoteException

getNodeFromCacheTable

public Node getNodeFromCacheTable(java.lang.String nodeId)
                           throws java.rmi.RemoteException

get node for nodeId from the cache table returns null if node not found

Specified by:

getNodeFromCacheTable in interface HashtableServer

Parameters:

nodeId -

Returns:

Throws:

java.rmi.RemoteException

cachePut

public ResultObject cachePut(java.lang.String nodeId,
                             Node node,
                             int masterCopySite,
                             long storageSystemThreadId)

Once a node has been fetched for caching, insert into cache table.

Specified by:

cachePut in interface HashtableServer

Parameters:

nodeId -

node -

masterCopySite -

storageSystemThreadId -

Returns:

cachePut

public java.util.Vector<ResultObject> cachePut(java.util.Map<java.lang.Integer,java.util.Vector<Node>> nodes,
                                               long storageSystemThreadId)

Bulk call for cachePut

Specified by:

cachePut in interface HashtableServer

Parameters:

nodes - - Map of master site v/s list of nodes obtained from that master site

storageSystemThreadId -

Returns:

cacheInvalidate

public void cacheInvalidate(java.lang.String nodeId)

Master server invokes this function on a remote server when asking it to invalidate its cache copy

Specified by:

cacheInvalidate in interface HashtableServer

Parameters:

nodeId - - node for which invalidation has to take place

cacheEvict

public Node cacheEvict(java.lang.String nodeId)

cache eviction thread invokes this method when removing a copy from the cache table (cache replacement)

Parameters:

nodeId -

Returns:

cacheEvictMasterNotify

public void cacheEvictMasterNotify(java.lang.String cachingServerId,
                                   java.util.Hashtable<java.lang.String,java.lang.Long> evictedNodes)
                            throws java.rmi.RemoteException

cache eviction thread invokes this method on the master site informing it of the cache eviction

Specified by:

cacheEvictMasterNotify in interface HashtableServer

Parameters:

cachingServerId -

evictedNodes -

Throws:

java.rmi.RemoteException

getNodeForCaching

public Node getNodeForCaching(java.lang.String nodeId,
                              int cachingSite)

Remote server invokes this method on the master site when requesting a cache copy

Specified by:

getNodeForCaching in interface HashtableServer

Parameters:

nodeID -

cachingSite -

Returns:

getNodesForCaching

public java.util.Vector<Node> getNodesForCaching(java.util.Vector<java.lang.String> nodeIds,
                                                 int cachingSite)

Bulk call for getNodeForCaching

Specified by:

getNodesForCaching in interface HashtableServer

writeThroughToCache

public void writeThroughToCache(java.lang.String paramString,
                                java.lang.Object value)

write through to local cache, so that master does need to invalidate the copy on put

Specified by:

writeThroughToCache in interface HashtableServer

Parameters:

paramString -

value -

writeThroughToCacheBulk

public void writeThroughToCacheBulk(java.util.concurrent.ConcurrentHashMap<java.lang.String,Node> map)

bulk call for writeThroughToCache

Specified by:

writeThroughToCacheBulk in interface HashtableServer

Parameters:

map -

getLocalNodes

public java.util.Vector<ResultObject> getLocalNodes(java.util.Vector<java.lang.String> nodeIds,
                                                    long storageSystemThreadId)

Storage system invokes this method on the server when requesting nodes and status for those nodes which are not available Only used in caching case

Specified by:

getLocalNodes in interface HashtableServer

Parameters:

nodeIds -

Returns:

getNodeFromTable

public Node getNodeFromTable(java.lang.String nodeId)
                      throws java.rmi.RemoteException

get a node from the table

Specified by:

getNodeFromTable in interface HashtableServer

Parameters:

nodeId -

Returns:

Throws:

java.rmi.RemoteException

contains

public boolean contains(java.lang.String key)

Check if the table contains a given key

Specified by:

contains in interface HashtableServer

Parameters:

key -

Returns:

getAllNodes

public java.util.Vector<Node> getAllNodes()

Get all nodes present in the main table (does not include cache table)

Specified by:

getAllNodes in interface HashtableServer

Returns:

getAllKeys

public java.util.Vector<java.lang.String> getAllKeys()

Get all node ids present in the main table (does not include cache table)

Specified by:

getAllKeys in interface HashtableServer

Returns:

getStats

public java.lang.String getStats()

Get the stats, called after program run terminates

Specified by:

getStats in interface HashtableServer

Returns:

clearStatContainers

public void clearStatContainers()

Clear stat containers

Specified by:

clearStatContainers in interface HashtableServer

loadNodes

public void loadNodes(java.util.Vector<Node> nodes)
               throws java.rmi.RemoteException

To load initial nodes into the table, used by the file loader

Specified by:

loadNodes in interface HashtableServer

Parameters:

nodes -

Throws:

java.rmi.RemoteException

getServerId

public int getServerId()
                throws java.rmi.RemoteException

Specified by:

getServerId in interface HashtableServer

Throws:

java.rmi.RemoteException

getNumServers

public int getNumServers()
                  throws java.rmi.RemoteException

Specified by:

getNumServers in interface HashtableServer

Throws:

java.rmi.RemoteException

setNumServers

public void setNumServers(int n)
                   throws java.rmi.RemoteException

Specified by:

setNumServers in interface HashtableServer

Throws:

java.rmi.RemoteException

relocate

public ResultObject relocate(int nodeId,
                             java.lang.String serverName)

called on the homesite when relocating a node to a remote server homesite makes a note of it in the location table

Specified by:

relocate in interface HashtableServer

Parameters:

nodeId -

serverName -

Returns:

locationChange

public void locationChange(int nodeId,
                           java.lang.String servername)

Inform the homesite that a node has been relocated. homesite makes a note of it in the location table and removes node from main table

Specified by:

locationChange in interface HashtableServer

Parameters:

nodeId -

servername -

lock

public ResultObject lock(int nodeId)
                  throws java.rmi.RemoteException

Lock an object to prevent its relocation

Specified by:

lock in interface HashtableServer

Parameters:

nodeId -

Returns:

Throws:

java.rmi.RemoteException

removeLocationTableEntry

public void removeLocationTableEntry(java.lang.String key)

Remove a key from the location table

Specified by:

removeLocationTableEntry in interface HashtableServer

Parameters:

key -

getClusterMeasures

public ClusterMeasures getClusterMeasures()

Specified by:

getClusterMeasures in interface HashtableServer

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

Throws:

java.lang.Exception