zeta.handler
Class RequestWorkUnitHandler

java.lang.Object
  |
  +--zeta.handler.RequestWorkUnitHandler

All Implemented Interfaces:

GetHandler

public class RequestWorkUnitHandler

extends java.lang.Object

implements GetHandler

Handles a GET request for new work units. The request must contains the following parameters:

• user - name of the resource provider.
• email - email of the resource provider.
• team - name of the team where the resource provider is join in.
• task - name of task for the work units.
• size - size of the work units.
• number_of_work_units - number of work units which are requested.
• hostname - name of the host of the resource provider.
• hostaddr - TCP/IP address of the host of the resource provider.
• version - version number of the task.
• os_name - name of the operating system of the resource provider.
• os_version - version of the operating system of the resource provider.
• os_arch - processor architecture of the requested resource.

The response contains the parameters (work_unit_id, size) of the new work units. The new work units are generated by the following algorithm:

1. Set the number requested work units equal to the number of defined processors of the specified hostname if the number of defined processors is larger than the number of requested work units.
2. Add all active work units which are reserved for the specified task, hostname and hostaddr to the response. Note: the global parameter 'work_unit_id_complete' was used to reduce the evaluation time.
3. Add all active work units which are reserved for the specified task, hostname, user and email to the response. This is important for resources which used DHCP. Note: the global parameter 'work_unit_id_complete' was used to reduce the evaluation time.
4. Register a new resource provider if the pair (user, email) is unknown.
5. Update the registered TCP/IP address of the resource hostname by hostaddr if the hostaddr is different to the registered address and the resource provider is equal to the pair (user, email).
6. Register a new resource (hostname,hostaddr,os_name,os_version,os_arch) if the pair (hostname,hostaddr) is unknown.
7. Add and reserve work units for the task from the recomputation pool if the resource provider is activated for recomputations.
8. Add and reserve new work units for the specified task, resource and his provider. The new identifications of the work units depend on the largest known identification, the size and the globale parameter 'work_unit_id_overlap'. Note: The sizes of the new work units can be different whether they have the same size.

Field Summary

private static int	DEFAULT_WORK_UNIT_SIZE Default size of a new work unit.
private static int	MAX_WORK_UNITS_TRUST0 Maximal number of work units which can be requested by one client.
private static int	MAX_WORK_UNITS_TRUST1
private static int	MAX_WORK_UNITS_TRUST2
private ZetaServlet	servlet Servlet which owns this handler.
private java.util.Map	userMap Maps a key (server-ID,name,email) of an user to the user-ID.
private java.util.Map	workstationMap Maps a key (server-ID,user-ID) of a workstation to a list of workstation-IDs.
private java.util.Map	workUnitSize Defined sizes for specified tasks and work unit sizes.

Constructor Summary

RequestWorkUnitHandler(ZetaServlet servlet)

Method Summary

void	doGet(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp) Handles a GET request for new work units.
private int	getWorkUnitSize(int taskId, java.lang.String sizeOfWorkUnit, long workUnitId, java.sql.Statement stmt) Returns the size of a work unit for a specified taskId, size and workUnitId.
private void	insertWorkUnitsIntoDatabase(WorkUnit[] workUnits, TaskRequestWorkUnitProcessor processor, int taskId, int serverId, int workstationId, java.lang.String version, int userId)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_WORK_UNIT_SIZE

private static final int DEFAULT_WORK_UNIT_SIZE

Default size of a new work unit.

See Also:

Constant Field Values

MAX_WORK_UNITS_TRUST0

private static final int MAX_WORK_UNITS_TRUST0

Maximal number of work units which can be requested by one client.

See Also:

Constant Field Values

MAX_WORK_UNITS_TRUST1

private static final int MAX_WORK_UNITS_TRUST1

See Also:

Constant Field Values

MAX_WORK_UNITS_TRUST2

private static final int MAX_WORK_UNITS_TRUST2

See Also:

Constant Field Values

workUnitSize

private java.util.Map workUnitSize

Defined sizes for specified tasks and work unit sizes.

userMap

private java.util.Map userMap

Maps a key (server-ID,name,email) of an user to the user-ID.

workstationMap

private java.util.Map workstationMap

Maps a key (server-ID,user-ID) of a workstation to a list of workstation-IDs.

servlet

private ZetaServlet servlet

Servlet which owns this handler.

Constructor Detail

RequestWorkUnitHandler

public RequestWorkUnitHandler(ZetaServlet servlet)

Parameters:

servlet - servlet which owns this handler.

Method Detail

doGet

public void doGet(javax.servlet.http.HttpServletRequest req,
                  javax.servlet.http.HttpServletResponse resp)
           throws javax.servlet.ServletException,
                  java.sql.SQLException,
                  java.io.IOException

Handles a GET request for new work units. The request req must contains the following parameters:

• user - name of the resource provider.
• email - email of the resource provider.
• team - name of the team where the resource provider is join in.
• task - name of task for the work units.
• size - size of the work units.
• work_units - number of work units which are requested.
• hostname - name of the host of the resource provider.
• hostaddr - TCP/IP address of the host of the resource provider.
• version - version number of the task.
• os_name - name of the operating system of the resource provider.
• os_version - version of the operating system of the resource provider.
• os_arch - processor architecture of the requested resource.

The response resp contains the parameters (work_unit_id, size) of the new work units.

Specified by:

doGet in interface GetHandler

javax.servlet.ServletException

java.sql.SQLException

java.io.IOException

insertWorkUnitsIntoDatabase

private void insertWorkUnitsIntoDatabase(WorkUnit[] workUnits,
                                         TaskRequestWorkUnitProcessor processor,
                                         int taskId,
                                         int serverId,
                                         int workstationId,
                                         java.lang.String version,
                                         int userId)
                                  throws javax.servlet.ServletException,
                                         java.sql.SQLException

javax.servlet.ServletException

java.sql.SQLException

getWorkUnitSize

private int getWorkUnitSize(int taskId,
                            java.lang.String sizeOfWorkUnit,
                            long workUnitId,
                            java.sql.Statement stmt)
                     throws java.sql.SQLException

Returns the size of a work unit for a specified taskId, size and workUnitId.

Parameters:

taskId - identification of the task.

workUnitId - id of the work unit

Returns:

the size of a work unit for a specified taskId, size and workUnitId.

java.sql.SQLException