Options for TAO Components

Overview

TAO is an extremely flexible ORB that can be configured to meet a wide range of application requirements. There are two primary mechanisms for configuring TAO's behaviors:

Configurations that are global to an ORB, such as a Name Service IOR or the default stringified IOR format an ORB generates, are configured via environment variables or command-line option flags passed to the ORB_init() call. The internal structure for command-line options is the traditional argc/argv vector of strings style popularized by C/C++ and Unix. By convention, ORB_init() will consume any options that it recognizes, removing them from argv, whereas unrecognized options will not be removed.
Users can also modify the internal behaviors of an ORB by dynamically linking ORB plug-ins, such as client/server connection strategies, via a svc.conf file. These ORB plug-ins can be fine-tuned by specifying their options in the svc.conf file. TAO provides several default plug-ins to deploy resource management strategies, client/server strategies, and communication protocols that can be further customized via the svc.conf file options described in this page. Advanced users can also develop their own plug-ins to customize TAO. A svc.conf file, however, is not required to run TAO programs since TAO provides a set of built-in strategies configured for use with common use cases. Many of the default configuratiions for these built-in strategies can also be customized when TAO is compiled.

Environment Variables

The following environment variables are supported by TAO:

Environment Variable Description

NameServiceIOR which Specifies which IOR the Naming Service is listening on.

NameServicePort which Specifies which port the Naming Service is listening on for multicast requests.

TradingServiceIOR which Specifies which IOR the Trading Service is listening on.

TradingServicePort which Specifies which port the Trading Service is listening on for multicast requests.

ImplRepoServiceIOR which Specifies the IOR of an Implementation Repository.

ImplRepoServicePort which Specifies which port the Implementation Repository is listening on for multicast requests.

Environment Variable	Description
`NameServiceIOR` which	Specifies which IOR the Naming Service is listening on.
`NameServicePort` which	Specifies which port the Naming Service is listening on for multicast requests.
`TradingServiceIOR` which	Specifies which IOR the Trading Service is listening on.
`TradingServicePort` which	Specifies which port the Trading Service is listening on for multicast requests.
`ImplRepoServiceIOR` which	Specifies the IOR of an Implementation Repository.
`ImplRepoServicePort` which	Specifies which port the Implementation Repository is listening on for multicast requests.

Types of Options

The following components can be tuned via the different options mentioned above:

CORBA::ORB
TAO_Default_Resource_Factory
TAO_Advanced_Resource_Factory
TAO_Default_Server_Strategy_Factory
TAO_Default_Client_Strategy_Factory
RT_ORB_Loader
The details of the options are mentioned below.

`CORBA::ORB`

Typically, the following options are set via command line parameters that are eventually passed to CORBA::ORB_init ().

Note: -ORBGlobalCollocation flag has been merged with -ORBCollocation.

Option Description

-ORBSvcConf config filename Specifies the name of the file from which it will read dynamic service configuration directives ala ACE's Service Configurator. By default, a service configurator-based application will look for a file named "svc.conf" in the current directory.

-ORBSvcConfDirective directivestring Specifies a service configuration directive, which is passed to ACE's Service Configurator. You can pass multiple of these options on the same command-line.

-ORBServiceConfigLoggerKey logger key Set the logger key in the ACE_Service_Config framework. Equivalent to the -k option on the ACE service configurator class.

-ORBDaemon Specifies that the ORB should daemonize itself.

-ORBDebug Turns on the output of debugging messages within ACE's Service Configurator componentry.

-ORBDebugLevel level Control the level of debugging in the ORB. Higher number produce more output (try 10).

-ORBEndpoint endpoint Tells the ORB to listen for requests on the interface specified by endpoint. Endpoints are specified using a URL style format. An endpoint has the form:
protocol://V.v@addr1,...,W.w@addrN
where V.v and W.w are optional protcol versions for each address. An example of an IIOP endpoint is:
iiop://hostname:port
Sets of endpoints may be specified using multiple -ORBEndpoint options or by delimiting endpoints with a semi-colon (;). For example,
-ORBEndpoint iiop://localhost:9999 -ORBEndpoint uiop:///tmp/mylocalsock -ORBEndpoint shmiop://10002
is equivalent to:
-ORBEndpoint 'iiop://localhost:9999;uiop:///tmp/mylocalsock;shmiop://10002'
Notice the single quotes (') in the latter option specification. Single quotes are needed to prevent the shell from interpreting text after the semi-colon as another command to run.
If an endpoint is specified without an addr such as the following:
-ORBEndpoint uiop:// -ORBEndpoint shmiop://
then a default endpoint will be created for the specified protocol.
This is a server side option.

-ORBObjRefStyle which Specifies the user-visible style of object references. The range of values is IOR (default), which is the traditional nonsensical object reference, or URL, which looks more like a URL.

-ORBRcvSock receive buffer size Specify the size of the socket receive buffer as a positive, non-zero integer. If not specified, the ACE_DEFAULT_MAX_SOCKET_BUFSIZ default is used.

-ORBSndSock send buffer size Specify the size of the socket send buffer as a positive, non-zero integer. If not specified, the ACE_DEFAULT_MAX_SOCKET_BUFSIZ default is used.

-ORBNodelay boolean (0|1) Enable or disable the TCP_NODELAY option. By default, TCP_NODELAY is enabled.

-ORBNameServicePort portspec Specifies which port the Naming Service is listening on for multicast requests. By default, TAO_DEFAULT_NAME_SERVICE_REQUEST_PORT, which is 10013 is used.

-ORBTradingServicePort portspec Specifies to which port the Trading Service is listening on for multicast requests. By default, TAO_DEFAULT_TRADING_SERVICE_REQUEST_PORT which is 10016 is used.

-ORBImplRepoServicePort portspec Specifies to which port the Implementation Repository is listening on for multicast requests. By default, TAO_DEFAULT_IMPLREPO_SERVER_REQUEST_PORT which is 10018 is to be used.

-ORBMulticastDiscoveryEndpoint end_point Specifies the endpoint that should be used for locating the Naming Service through multicast. end_point is of the form ip-number:port-number (e.g., "tango.cs.wustl.edu:1234" or "128.252.166.57:1234"). If there is no ':' in the end_point it is assumed to be a port number, with the IP address being INADDR_ANY.

-ORBCollocation global/per-orb/no Specifies the use of collocation object optimization. If global is specified, objects in the same process will be treated as collocated. If per-orb is specified, only objects in the same ORB are treated as collocated. When no is specified, no objects are treated as collocated. Default is global.

-ORBCollocationStrategy thru_poa/direct Specifies what kind of collocated object to use. If the thru_poa strategy is used, TAO uses the collocation object implementation that respects POA's current state and policies. When using the direct strategy, method invocations on collocated objects become direct calls to servant without checking POA's status (which translates to better performance.) Notice that the interfaces that you wish to use direct collocation with must be compiled with -Gd. Default is thru_poa.

-ORBPreconnect endpoint Pre-establishes a blocking connection to each listed endpoint. If a connection cannot be established the failed preconnection will be ignored and the next preconnection in the list will be processed. Successful and unsuccessful preconnections will be displayed if a debugging level greater than or equal to one is specified by using the -ORBDebugLevel option. Listing the same combination multiple times will properly establish multiple connections to that endpoint. The -ORBPreconnect option uses the same endpoint format as the -ORBEndpoint option.
This is a client-side option.
-ORBPreconnect is deprecated. This option will be removed in the near future. The Real-Time CORBA standard validate_connection() method should be used instead.

-ORBCDRTradeoff maxsize Control the strategy to tradeoff between copy vs. no copy marshalling of octet sequences. If an octet sequence is smaller than maxsize and the current message block contains enough space for it the octet sequence is copied instead of appended to the CDR stream. By default, ACE_DEFAULT_CDR_MEMORY_TRADEOFF is used.

-ORBSkipServiceConfigOpen Do not call the ACE_Service_Config::open method when initializing the ORB. This option is generally only useful when dynamically loading the ORB.
This option is deprecated. It is no longer needed since the Service Configurator is now reentrant and thread-safe.

-ORBDottedDecimalAddresses boolean (0|1) Use the dotted decimal notation for addresses. This option helps to work around broken DNS implementations and may also reduce the time spent resolving IP addresses. By default domain names are used in IORs.

-ORBInitRef ObjectId=IOR Allows specification of an arbitrary object reference for an initial service. The IOR could be in any one of the following formats : OMG IOR, URL, corbaloc (including uioploc) or file. corbaloc is a multiple end-point IOR understood by the string_to_object () method and used as a boot-strapping mechanism by the resolve_initial_references () method. The mappings specified through this argument override the orb-install-time defaults. The file://pathname interprets the contents of the pathname file as an object reference in any of the above formats.

-ORBDefaultInitRef IOR prefix This argument allows resolution of initial references not explicitly specified with -ORBInitRef. It requires a URL prefix that, after appending a slash '/' ('|' for UIOP pluggable protocol) and a simple object key, forms a new URL to identify an initial object reference. The URL prefix format currently supported is corbaloc.

-ORBStdProfileComponents boolean (0|1) If 0 then the ORB does not generate the OMG standardized profile components, such as the ORB type and code sets. Notice that the presence of this components is optional in GIOP 1.1 The default value is controlled by a compile-time flag (check orbconf.h).

-ORBResources which This option is deprecated, since this option has almost negligible effect on the ORB. The right type of resources are selected by the ORB during runtime. For example the memory for the output datapath always defaults to TSS. The inour data path always defaults to stack for small messages and global pool for larger messages. There was no effect with the use of this option.

-ORBUseIMR boolean (0|1) This argument specifies that for POAs with the PERSISTENT policy, that the Implementation Repository should be used for notification of startup and shutdown and Object References should be changed to use the Implementation Repository also.

-ORBLogFile log file name Causes all ACE_DEBUG and ACE_ERROR output to be redirected to the specified file.

-ORBSingleReadOptimization boolean (0|1) This option controls single read optimzations when reading requests. If this option is off, the ORB will do two reads to read a request. One to read the request header and the other to read the request payload. If this option is on, the ORB will do a read of size TAO_MAXBUFSIZE, hoping to read the entire request. However, in this case, there is a chance of reading more than one request. If any additional requests have been read, they are queued up for processing later.
This option defaults to 1 because it can provide better performance since one less read is performed. However, in the case of RT-CORBA, this option should be set to 0. Consider the following scenario: two requests are read from one socket; the additional request is queued; a Reactor notify is dispatch to awake a follower threads; at this time, new requests arrive on others sockets of higher priority; however, since notifies are given preferences over normal I/O, the lower priority queued message will be processed before the newly arrived higher priority request.

-ORBListenEndpoints endpoint This Option is similar to ORBEndPoint option described above. The ORBEndpoint option would be deprecated in later versions on TAO. This option is introduced with Object Reference Template Specification.

-ORBId ORB_NAME This option allows setting the name of an ORB as the Option name suggests.

-ORBServerId server_id This option allows setting a name/id to a server to uniquely identify a server to the Implementation Repository.

Option	Description
`-ORBSvcConf` config filename	Specifies the name of the file from which it will read dynamic service configuration directives ala ACE's Service Configurator. By default, a service configurator-based application will look for a file named "svc.conf" in the current directory.
`-ORBSvcConfDirective` directivestring	Specifies a service configuration directive, which is passed to ACE's Service Configurator. You can pass multiple of these options on the same command-line.
`-ORBServiceConfigLoggerKey` logger key	Set the logger key in the `ACE_Service_Config` framework. Equivalent to the `-k` option on the ACE service configurator class.
`-ORBDaemon`	Specifies that the ORB should daemonize itself.
`-ORBDebug`	Turns on the output of debugging messages within ACE's Service Configurator componentry.
`-ORBDebugLevel` level	Control the level of debugging in the ORB. Higher number produce more output (try 10).
`-ORBEndpoint` endpoint	Tells the ORB to listen for requests on the interface specified by endpoint. Endpoints are specified using a URL style format. An endpoint has the form: `protocol://V.v@addr1,...,W.w@addrN` where `V.v` and `W.w` are optional protcol versions for each address. An example of an IIOP endpoint is: `iiop://hostname:port` Sets of endpoints may be specified using multiple `-ORBEndpoint` options or by delimiting endpoints with a semi-colon (;). For example, `-ORBEndpoint iiop://localhost:9999 -ORBEndpoint uiop:///tmp/mylocalsock -ORBEndpoint shmiop://10002` is equivalent to: `-ORBEndpoint 'iiop://localhost:9999;uiop:///tmp/mylocalsock;shmiop://10002'` Notice the single quotes (') in the latter option specification. Single quotes are needed to prevent the shell from interpreting text after the semi-colon as another command to run. If an endpoint is specified without an `addr` such as the following: `-ORBEndpoint uiop:// -ORBEndpoint shmiop://` then a default endpoint will be created for the specified protocol. This is a server side option.
`-ORBObjRefStyle` which	Specifies the user-visible style of object references. The range of values is `IOR` (default), which is the traditional nonsensical object reference, or `URL`, which looks more like a URL.
`-ORBRcvSock` receive buffer size	Specify the size of the socket receive buffer as a positive, non-zero integer. If not specified, the ACE_DEFAULT_MAX_SOCKET_BUFSIZ default is used.
`-ORBSndSock` send buffer size	Specify the size of the socket send buffer as a positive, non-zero integer. If not specified, the ACE_DEFAULT_MAX_SOCKET_BUFSIZ default is used.
`-ORBNodelay` boolean (0\|1)	Enable or disable the TCP_NODELAY option. By default, TCP_NODELAY is enabled.
`-ORBNameServicePort` portspec	Specifies which port the Naming Service is listening on for multicast requests. By default, TAO_DEFAULT_NAME_SERVICE_REQUEST_PORT, which is 10013 is used.
`-ORBTradingServicePort` portspec	Specifies to which port the Trading Service is listening on for multicast requests. By default, TAO_DEFAULT_TRADING_SERVICE_REQUEST_PORT which is 10016 is used.
`-ORBImplRepoServicePort` portspec	Specifies to which port the Implementation Repository is listening on for multicast requests. By default, TAO_DEFAULT_IMPLREPO_SERVER_REQUEST_PORT which is 10018 is to be used.
`-ORBMulticastDiscoveryEndpoint` end_point	Specifies the endpoint that should be used for locating the Naming Service through multicast. end_point is of the form ip-number:port-number (e.g., "tango.cs.wustl.edu:1234" or "128.252.166.57:1234"). If there is no ':' in the end_point it is assumed to be a port number, with the IP address being INADDR_ANY.
`-ORBCollocation` global/per-orb/no	Specifies the use of collocation object optimization. If global is specified, objects in the same process will be treated as collocated. If per-orb is specified, only objects in the same ORB are treated as collocated. When no is specified, no objects are treated as collocated. Default is global.
`-ORBCollocationStrategy` thru_poa/direct	Specifies what kind of collocated object to use. If the thru_poa strategy is used, TAO uses the collocation object implementation that respects POA's current state and policies. When using the direct strategy, method invocations on collocated objects become direct calls to servant without checking POA's status (which translates to better performance.) Notice that the interfaces that you wish to use direct collocation with must be compiled with `-Gd`. Default is thru_poa.
`-ORBPreconnect` endpoint	Pre-establishes a blocking connection to each listed endpoint. If a connection cannot be established the failed preconnection will be ignored and the next preconnection in the list will be processed. Successful and unsuccessful preconnections will be displayed if a debugging level greater than or equal to one is specified by using the `-ORBDebugLevel` option. Listing the same combination multiple times will properly establish multiple connections to that endpoint. The `-ORBPreconnect` option uses the same endpoint format as the `-ORBEndpoint` option. This is a client-side option. -ORBPreconnect is deprecated. This option will be removed in the near future. The Real-Time CORBA standard `validate_connection()` method should be used instead.
`-ORBCDRTradeoff` maxsize	Control the strategy to tradeoff between copy vs. no copy marshalling of octet sequences. If an octet sequence is smaller than maxsize and the current message block contains enough space for it the octet sequence is copied instead of appended to the CDR stream. By default, ACE_DEFAULT_CDR_MEMORY_TRADEOFF is used.
`-ORBSkipServiceConfigOpen`	Do not call the `ACE_Service_Config::open` method when initializing the ORB. This option is generally only useful when dynamically loading the ORB. This option is deprecated. It is no longer needed since the Service Configurator is now reentrant and thread-safe.
`-ORBDottedDecimalAddresses` boolean (0\|1)	Use the dotted decimal notation for addresses. This option helps to work around broken DNS implementations and may also reduce the time spent resolving IP addresses. By default domain names are used in IORs.
`-ORBInitRef` ObjectId=IOR	Allows specification of an arbitrary object reference for an initial service. The IOR could be in any one of the following formats : OMG IOR, URL, corbaloc (including uioploc) or file. corbaloc is a multiple end-point IOR understood by the string_to_object () method and used as a boot-strapping mechanism by the resolve_initial_references () method. The mappings specified through this argument override the orb-install-time defaults. The file://pathname interprets the contents of the pathname file as an object reference in any of the above formats.
`-ORBDefaultInitRef` IOR prefix	This argument allows resolution of initial references not explicitly specified with -ORBInitRef. It requires a URL prefix that, after appending a slash '/' ('\|' for UIOP pluggable protocol) and a simple object key, forms a new URL to identify an initial object reference. The URL prefix format currently supported is corbaloc.
`-ORBStdProfileComponents` boolean (0\|1)	If 0 then the ORB does not generate the OMG standardized profile components, such as the ORB type and code sets. Notice that the presence of this components is optional in GIOP 1.1 The default value is controlled by a compile-time flag (check orbconf.h).
`-ORBResources` which	This option is deprecated, since this option has almost negligible effect on the ORB. The right type of resources are selected by the ORB during runtime. For example the memory for the output datapath always defaults to TSS. The inour data path always defaults to stack for small messages and global pool for larger messages. There was no effect with the use of this option.
`-ORBUseIMR` boolean (0\|1)	This argument specifies that for POAs with the PERSISTENT policy, that the Implementation Repository should be used for notification of startup and shutdown and Object References should be changed to use the Implementation Repository also.
`-ORBLogFile` log file name	Causes all ACE_DEBUG and ACE_ERROR output to be redirected to the specified file.
`-ORBSingleReadOptimization` boolean (0\|1)	This option controls single read optimzations when reading requests. If this option is off, the ORB will do two reads to read a request. One to read the request header and the other to read the request payload. If this option is on, the ORB will do a read of size TAO_MAXBUFSIZE, hoping to read the entire request. However, in this case, there is a chance of reading more than one request. If any additional requests have been read, they are queued up for processing later. This option defaults to 1 because it can provide better performance since one less read is performed. However, in the case of RT-CORBA, this option should be set to 0. Consider the following scenario: two requests are read from one socket; the additional request is queued; a Reactor notify is dispatch to awake a follower threads; at this time, new requests arrive on others sockets of higher priority; however, since notifies are given preferences over normal I/O, the lower priority queued message will be processed before the newly arrived higher priority request.
`-ORBListenEndpoints` endpoint	This Option is similar to ORBEndPoint option described above. The ORBEndpoint option would be deprecated in later versions on TAO. This option is introduced with Object Reference Template Specification.
`-ORBId` ORB_NAME	This option allows setting the name of an ORB as the Option name suggests.
`-ORBServerId` server_id	This option allows setting a name/id to a server to uniquely identify a server to the Implementation Repository.

`TAO_Default_Resource_Factory`

Typically, the following options are set via the service configurator (svc.conf) file. The following line in the svc.conf file (all in one line)
static Resource_Factory "[list of options]"
would load all the options listed within "".

Option Description

-ORBResources which This option is deprecated, since this option has almost negligible effect on the ORB. The right type of resources are selected by the ORB during runtime. For example the memory for the output datapath always defaults to TSS. The inour data path always defaults to stack for small messages and global pool for larger messages. There was no effect with the use of this option.

-ORBReactorMaskSignals 0/1 ACE select reactors mask signals during upcalls to the event handlers. This is only useful if the application is going to trap those signals and handle them in any way. Disabling the mask can improve performance by reducing the number of kernel level locks.

-ORBProtocolFactory factory Specify which pluggable protocol factory to load. By default, only the factory for the IIOP protocol (IIOP_Factory is loaded.
For example, if some protocol called Foo whose factory was called Foo_Factory was available, then it could be loaded into TAO by specifying -ORBProtocolFactory Foo_Factory in the service configurator file. The Foo pluggable protocol would then be available for use.

-ORBIORParser parser Name an IOR Parser to load. IOR Parsers are used to interpret strings passed to ORB::string_to_object(). By default the ORB can handle multiple string formats, including IOR:, corbaloc:, corbaname:, and file:. The application developer can add new IOR formats using this option.

-ORBConnectionCachingStrategy type This option is deprecated. Use -ORBConnectionPurgingStrategy instead.

-ORBConnectionPurgingStrategy type Opened connections are added to the transport cache so they can be reused. However, if a process continues to run and these connections are not reused, the cache will continue to grow. Therefore, before each new connection, the cache is checked and purged if it has reached the limit specified by the -ORBConnectionCacheMax option or the system default if that option was not used. The possible values for type are lru, lfu, fifo and null. The default is LRU (Least Recently Used). The others LFU (Least Frequently Used), FIFO (First In First Out), and null (No connections are purged) are contained within the TAO Strategies library.

-ORBConnectionCacheMax limit The transport cache will grow to a maximum of the specified limit. The default is system dependent, but can be overridden at compile time by defining the preprocessor macro TAO_CONNECTION_CACHE_MAXIMUM.

-ORBMuxedConnectionMax number The transport cache allows only specified number of connections-per-QoS property to be added to connection cache. Threads not getting the connections will wait for the connections to be released. This options is more useful for transports using a muxed connection strategy and want control on the number of connections that are created by the active threads.

-ORBConnectionCachePurgePercentage percent If the transport cache is purged, the specified percentage (20 by default) of the total number of connections cached will be closed.

-ORBPurgePercentage percent This option is deprecated and will automatically forward to -ORBConnectionCachePurgePercentage.

-ORBConnectionCacheLock locktype Specify the type of lock to be used by the Connection Cache. Possible values for lock type are thread, which specifies that an inter-thread mutex is used to guarantee exclusive access, and null, which specifies that no locking be performed. The default is thread.

-ORBFlushingStrategy type By default TAO provides three strategies to flush queued messages. The leader_follower strategy uses the Reactor and non-blocking I/O to send the outgoing messages, this strategy participates in the Leader/Followers protocol to synchronize access to the Reactor. The reactive strategy uses the Reactor but does not take part in the Leader/Followers protocol, thus it is better used only in single threaded applications. Finally, the blocking strategy flushes the queue as soon as it becomes "full", and blocks the thread until all the data is sent.

Option	Description
`-ORBResources` which	This option is deprecated, since this option has almost negligible effect on the ORB. The right type of resources are selected by the ORB during runtime. For example the memory for the output datapath always defaults to TSS. The inour data path always defaults to stack for small messages and global pool for larger messages. There was no effect with the use of this option.
`-ORBReactorMaskSignals` 0/1	ACE select reactors mask signals during upcalls to the event handlers. This is only useful if the application is going to trap those signals and handle them in any way. Disabling the mask can improve performance by reducing the number of kernel level locks.
`-ORBProtocolFactory` factory	Specify which pluggable protocol factory to load. By default, only the factory for the IIOP protocol (`IIOP_Factory` is loaded. For example, if some protocol called `Foo` whose factory was called `Foo_Factory` was available, then it could be loaded into TAO by specifying `-ORBProtocolFactory Foo_Factory` in the service configurator file. The `Foo` pluggable protocol would then be available for use.
`-ORBIORParser` parser	Name an IOR Parser to load. IOR Parsers are used to interpret strings passed to `ORB::string_to_object()`. By default the ORB can handle multiple string formats, including `IOR:`, `corbaloc:`, `corbaname:`, and `file:`. The application developer can add new IOR formats using this option.
`-ORBConnectionCachingStrategy` type	This option is deprecated. Use -ORBConnectionPurgingStrategy instead.
`-ORBConnectionPurgingStrategy` type	Opened connections are added to the transport cache so they can be reused. However, if a process continues to run and these connections are not reused, the cache will continue to grow. Therefore, before each new connection, the cache is checked and purged if it has reached the limit specified by the -ORBConnectionCacheMax option or the system default if that option was not used. The possible values for type are lru, lfu, fifo and null. The default is LRU (Least Recently Used). The others LFU (Least Frequently Used), FIFO (First In First Out), and null (No connections are purged) are contained within the TAO Strategies library.
`-ORBConnectionCacheMax` limit	The transport cache will grow to a maximum of the specified limit. The default is system dependent, but can be overridden at compile time by defining the preprocessor macro TAO_CONNECTION_CACHE_MAXIMUM.
`-ORBMuxedConnectionMax` number	The transport cache allows only specified number of connections-per-QoS property to be added to connection cache. Threads not getting the connections will wait for the connections to be released. This options is more useful for transports using a muxed connection strategy and want control on the number of connections that are created by the active threads.
`-ORBConnectionCachePurgePercentage` percent	If the transport cache is purged, the specified percentage (20 by default) of the total number of connections cached will be closed.
`-ORBPurgePercentage` percent	This option is deprecated and will automatically forward to -ORBConnectionCachePurgePercentage.
`-ORBConnectionCacheLock` locktype	Specify the type of lock to be used by the Connection Cache. Possible values for lock type are `thread`, which specifies that an inter-thread mutex is used to guarantee exclusive access, and `null`, which specifies that no locking be performed. The default is thread.
`-ORBFlushingStrategy` type	By default TAO provides three strategies to flush queued messages. The `leader_follower` strategy uses the Reactor and non-blocking I/O to send the outgoing messages, this strategy participates in the Leader/Followers protocol to synchronize access to the Reactor. The `reactive` strategy uses the Reactor but does not take part in the Leader/Followers protocol, thus it is better used only in single threaded applications. Finally, the `blocking` strategy flushes the queue as soon as it becomes "full", and blocks the thread until all the data is sent.

`TAO_Default_Server_Strategy_Factory`

Typically, the following options are set via the service configurator (svc.conf) file. The following line in the svc.conf file (all in one line)
static Server_Strategy_Factory "[list of options]"
would load all the options listed within ""
Note: -ORBDemuxStrategy flag has been changed to -ORBSystemidPolicyDemuxStrategy and -ORBUseridPolicyDemuxStrategy.
Note: -ORBTableSize flag has been changed to -ORBActiveObjectMapSize.

Option Description

-ORBConcurrency which Specify which concurrency strategy to use. Range of values is reactive for a purely Reactor-driven concurrency strategy or thread-per-connection for creating a new thread to service each connection. The default is reactive.

-ORBThreadPerConnectionTimeout milliseconds In many platforms it is impossible to interrupt the server threads created by the thread-per-connection model. This is because these threads are blocked in read() operations (and not in select()). As a workaround, the server threads periodically poll the ORB to find out if they should shutdown. This option controls the period of the polling, expressed in milliseconds. Applications that do not shutdown, or that can otherwise ensure that no server threads will be running at shutdown (for example if all the clients terminate before the server) can disable the polling using the magic value INFINITE.
If the option is not provided then the ORB uses the compile time flag TAO_DEFAULT_THREAD_PER_CONNECTION_TIMEOUT, this flag also expresses the time in milliseconds (as a string constant) and the magic value "INFINITE" can be used to disable polling entirely. This yields a slight performance improvement (around 1%).

-ORBActiveObjectMapSize active object map size Specify the size of the active object map. If not specified, the default value is 64.

-ORBUseridPolicyDemuxStrategy user id policy based demultiplexing strategy Specify the demultiplexing lookup strategy to be used with the user id policy. The demultiplexing strategy can be one of dynamic or linear. This option defaults to use the dynamic strategy.

-ORBSystemidPolicyDemuxStrategy system id policy based demultiplexing strategy Specify the demultiplexing lookup strategy to be used with the system id policy. The demultiplexing strategy can be one of dynamic, linear, or active. This option defaults to use the dynamic strategy when -ORBAllowReactivationOfSystemids is true, and to active strategy when -ORBAllowReactivationOfSystemids is false.

-ORBUniqueidPolicyReverseDemuxStrategy unique id policy based reverse demultiplexing strategy Specify the reverse demultiplexing lookup strategy to be used with the unique id policy. The reverse demultiplexing strategy can be one of dynamic or linear. This option defaults to use the dynamic strategy.

-ORBAllowReactivationOfSystemids allows reactivation of system ids Specify whether system ids can be reactivated, i.e., once an id that was generated by the system has be deactivated, will the user reactivate a new servant using the old id. If the user is not going to use this feature, the IORs can be shortened, an extra comparison in the critical upcall path removed, and some memory on the server side can be saved. The ORBAllowReactivationOfSystemids can be 0 or 1. This option defaults to 1.

-ORBActiveHintInIds adds an active hint in ids Specify whether an active hint should be added to ids. With active hints, ids can be found quickly. However, they lead to larger IORs. Note that this option is disregarded -ORBAllowReactivationOfSystemids is set to 0. The -ORBActiveHintInIds can be 0 or 1. This option defaults to 1.

-ORBPoaMapSize poa map size Specify the size of the poa map. If not specified, the default value is 24.

-ORBPersistentidPolicyDemuxStrategy persistent id policy based demultiplexing strategy Specify the demultiplexing lookup strategy to be used with the persistent id policy. The demultiplexing strategy can be one of dynamic or linear. This option defaults to use the dynamic strategy.

-ORBTransientidPolicyDemuxStrategy transient id policy based demultiplexing strategy Specify the demultiplexing lookup strategy to be used with the transient id policy. The demultiplexing strategy can be one of dynamic, linear, or active. This option defaults to use the active strategy.

-ORBActiveHintInPOANames adds an active hint in poa names Specify whether an active hint should be added to poa names. With active hints, poa names can be found quickly. However, they lead to larger IORs. The -ORBActiveHintInPOANames can be 0 or 1. This option defaults to 1.

-ORBThreadFlags thread flags Specify the flags used for thread creation. Flags can be any logical-OR combination of THR_DETACHED, THR_BOUND, THR_NEW_LWP, THE_SUSPENDED. The default is THR_BOUND | THR_DETACHED .

-ORBPOALock lock type Specify the type of lock to be used for POA accesses. Possible values for lock type are thread, which specifies that an inter-thread mutex is used to guarantee exclusive access, and null, which specifies that no locking be performed. The default is thread.

Option	Description
`-ORBConcurrency` which	Specify which concurrency strategy to use. Range of values is `reactive` for a purely Reactor-driven concurrency strategy or `thread-per-connection` for creating a new thread to service each connection. The default is reactive.
`-ORBThreadPerConnectionTimeout` milliseconds	In many platforms it is impossible to interrupt the server threads created by the `thread-per-connection` model. This is because these threads are blocked in `read()` operations (and not in `select()`). As a workaround, the server threads periodically poll the ORB to find out if they should shutdown. This option controls the period of the polling, expressed in milliseconds. Applications that do not shutdown, or that can otherwise ensure that no server threads will be running at shutdown (for example if all the clients terminate before the server) can disable the polling using the magic value `INFINITE`. If the option is not provided then the ORB uses the compile time flag `TAO_DEFAULT_THREAD_PER_CONNECTION_TIMEOUT`, this flag also expresses the time in milliseconds (as a string constant) and the magic value `"INFINITE"` can be used to disable polling entirely. This yields a slight performance improvement (around 1%).
`-ORBActiveObjectMapSize` active object map size	Specify the size of the active object map. If not specified, the default value is 64.
`-ORBUseridPolicyDemuxStrategy` user id policy based demultiplexing strategy	Specify the demultiplexing lookup strategy to be used with the user id policy. The demultiplexing strategy can be one of `dynamic` or `linear`. This option defaults to use the `dynamic` strategy.
`-ORBSystemidPolicyDemuxStrategy` system id policy based demultiplexing strategy	Specify the demultiplexing lookup strategy to be used with the system id policy. The demultiplexing strategy can be one of `dynamic`, `linear`, or `active`. This option defaults to use the `dynamic` strategy when `-ORBAllowReactivationOfSystemids` is true, and to `active` strategy when `-ORBAllowReactivationOfSystemids` is false.
`-ORBUniqueidPolicyReverseDemuxStrategy` unique id policy based reverse demultiplexing strategy	Specify the reverse demultiplexing lookup strategy to be used with the unique id policy. The reverse demultiplexing strategy can be one of `dynamic` or `linear`. This option defaults to use the `dynamic` strategy.
`-ORBAllowReactivationOfSystemids` allows reactivation of system ids	Specify whether system ids can be reactivated, i.e., once an id that was generated by the system has be deactivated, will the user reactivate a new servant using the old id. If the user is not going to use this feature, the IORs can be shortened, an extra comparison in the critical upcall path removed, and some memory on the server side can be saved. The `ORBAllowReactivationOfSystemids` can be `0` or `1`. This option defaults to `1`.
`-ORBActiveHintInIds` adds an active hint in ids	Specify whether an active hint should be added to ids. With active hints, ids can be found quickly. However, they lead to larger IORs. Note that this option is disregarded `-ORBAllowReactivationOfSystemids` is set to `0`. The -ORBActiveHintInIds can be `0` or `1`. This option defaults to `1`.
`-ORBPoaMapSize` poa map size	Specify the size of the poa map. If not specified, the default value is 24.
`-ORBPersistentidPolicyDemuxStrategy` persistent id policy based demultiplexing strategy	Specify the demultiplexing lookup strategy to be used with the persistent id policy. The demultiplexing strategy can be one of `dynamic` or `linear`. This option defaults to use the `dynamic` strategy.
`-ORBTransientidPolicyDemuxStrategy` transient id policy based demultiplexing strategy	Specify the demultiplexing lookup strategy to be used with the transient id policy. The demultiplexing strategy can be one of `dynamic`, `linear`, or `active`. This option defaults to use the `active` strategy.
`-ORBActiveHintInPOANames` adds an active hint in poa names	Specify whether an active hint should be added to poa names. With active hints, poa names can be found quickly. However, they lead to larger IORs. The -ORBActiveHintInPOANames can be `0` or `1`. This option defaults to `1`.
`-ORBThreadFlags` thread flags	Specify the flags used for thread creation. Flags can be any logical-OR combination of `THR_DETACHED`, `THR_BOUND`, `THR_NEW_LWP`, `THE_SUSPENDED`. The default is `THR_BOUND \| THR_DETACHED` .
`-ORBPOALock` lock type	Specify the type of lock to be used for POA accesses. Possible values for lock type are `thread`, which specifies that an inter-thread mutex is used to guarantee exclusive access, and `null`, which specifies that no locking be performed. The default is `thread`.

`TAO_Default_Client_Strategy_Factory`

Typically, the following options are set via the service configurator (svc.conf) file. The following line in the svc.conf file (all in one line)
static Client_Strategy_Factory "[list of options]"
would load all the options listed within "".

Option Description

-ORBProfileLock which Specify the kind of synchronization primitive for the Profiles. Default is thread, which means that a regular thread mutex is used. The second option is null, which means a null lock is used. This makes sense in case of optimizations and is allowed when no forwarding is used or only a single threaded client.

-ORBClientConnectionHandler MT / ST / RW ST means use the single-threaded client connection handler, i.e., the leader follower model will not be used. However, ST does support nested upcalls and handling of new requests while waiting for the reply from a server.
MT means use the multi-threaded client connection handler which uses the leader follower model. This model allows the use of multiple threads with a single Reactor.
RW selects a strategy that simply blocks in recv() when waiting for a response from the server instead of waiting in the Reactor. The RW strategy only works when the application does not have to worry about new request showing up when waiting for a response. Further, this strategy cannot be used with AMI calls. Therefore, this strategy is appropriate only for "pure" synchronous clients. Note that applications with nested upcalls are not "pure" synchronous clients. Also note that this strategy will only effect two way calls, since there is no waiting for one way calls. This strategy can also be used in an application that is both a client and a server if the server side is handled by a separate thread and the client threads are "pure" clients.
Default for this option is MT.

-ORBTransportMuxStrategy EXCLUSIVE / MUXED EXCLUSIVE means that the Transport does not multiplex requests on a connection. At a time, there can be only one request pending on a connection.
MUXED means that Transport multiplexes more than one request at the same time on a connection. This option is often used in conjunction with Asynchronous Method Invocation, because multiple requests can be sent 'in bulk'.
Default for this option is MUXED.

-ORBConnectStrategy type TAO provides three strategies to connect to remote servers. The default leader_follower strategy uses the Reactor and non-blocking connects to connect and this strategy participates in the Leader/Followers protocol to synchronize access to the Reactor. The reactive strategy uses the Reactor for non-blocking connects but does not take part in the Leader/Followers protocol, thus it is better used only in single threaded applications. Finally, the blocked strategy as the name implies, blocks the thread until connection is complete. Some of the protocols in TAO viz. SHMIOP and SSLIOP can only use blocked strategy.

Option	Description
`-ORBProfileLock` which	Specify the kind of synchronization primitive for the Profiles. Default is `thread`, which means that a regular thread mutex is used. The second option is `null`, which means a null lock is used. This makes sense in case of optimizations and is allowed when no forwarding is used or only a single threaded client.
`-ORBClientConnectionHandler` MT / ST / RW	ST means use the single-threaded client connection handler, i.e., the leader follower model will not be used. However, ST does support nested upcalls and handling of new requests while waiting for the reply from a server. MT means use the multi-threaded client connection handler which uses the leader follower model. This model allows the use of multiple threads with a single Reactor. RW selects a strategy that simply blocks in recv() when waiting for a response from the server instead of waiting in the Reactor. The RW strategy only works when the application does not have to worry about new request showing up when waiting for a response. Further, this strategy cannot be used with AMI calls. Therefore, this strategy is appropriate only for "pure" synchronous clients. Note that applications with nested upcalls are not "pure" synchronous clients. Also note that this strategy will only effect two way calls, since there is no waiting for one way calls. This strategy can also be used in an application that is both a client and a server if the server side is handled by a separate thread and the client threads are "pure" clients. Default for this option is MT.
`-ORBTransportMuxStrategy` EXCLUSIVE / MUXED	EXCLUSIVE means that the Transport does not multiplex requests on a connection. At a time, there can be only one request pending on a connection. MUXED means that Transport multiplexes more than one request at the same time on a connection. This option is often used in conjunction with Asynchronous Method Invocation, because multiple requests can be sent 'in bulk'. Default for this option is MUXED.
`-ORBConnectStrategy` type	TAO provides three strategies to connect to remote servers. The default `leader_follower` strategy uses the Reactor and non-blocking connects to connect and this strategy participates in the Leader/Followers protocol to synchronize access to the Reactor. The `reactive` strategy uses the Reactor for non-blocking connects but does not take part in the Leader/Followers protocol, thus it is better used only in single threaded applications. Finally, the `blocked` strategy as the name implies, blocks the thread until connection is complete. Some of the protocols in TAO viz. SHMIOP and SSLIOP can only use blocked strategy.

`TAO_Advanced_Resource_Factory`

This factory is located in the TAO_Strategies library. It accepts the options below as well as those described above in the TAO_Default_Resource_Factory. This factory can be loaded dynamically using a service configurator directive of the form (all on one line):

dynamic Advanced_Resource_Factory Service_Object * TAO_Strategies:_make_TAO_Advanced_Resource_Factory () "-ORBReactorType select_st"

It can also be loaded statically by doing the following:

Add a #include "tao/Strategies/advanced_resource.h" to the file containing main()
Link the TAO_Strategies library into the executable
Specify a service configurator directive of the form: static Advanced_Resource_Factory "-ORBReactorType select_st"

You can omit the #include if you always use dynamic libraries.

Once you have loaded the Advanced_Resource_Factory, then directives for the Resource_Factory have no effect (and generate warnings telling you so).

Note: -ORBReactorLock flag has been superseded by -ORBReactorType.

Option Description

-ORBReactorType which Specify what kind of reactor the ORB uses. The default reactor is the ACE_TP_Reactor.

which Reactor

select_mt Use the multi-thread select-based reactor.

select_st Use the single-thread select-based reactor.

fl Use the FLReactor (FLTK-based).

wfmo Use the WFMO reactor (Win32 only).

msg_wfmo Use the MsgWFMO reactor (Win32 only).

tp Use the ACE_TP_Reactor, a select based thread-pool reactor which is the default.

-ORBReactorThreadQueue which Applies only to the ACE_TP_Reactor, i.e., when -ORBReactorType = tp, and specifies the order, last-in-first-out (which = LIFO), the default, or first-in-first-out (which = FIFO), in which waiting threads are selected to run by the ACE_Select_Reactor_Token.

-ORBInputCDRAllocator which Specify whether the ORB uses locked (which = thread) or lock-free (which = null) allocators for the incoming CDR buffers. Though null should give the optimal performance; we made the default thread. TAO optimizations for octet sequences will not work in all cases when the allocator does not have locks (for example if the octet sequences are part of a return value). Using locked allocators also allows the users to take advantage of the TAO octet sequence extensions to preserve the buffer after the upcall.

-ORBReactorRegistry registry_type This option is no longer supported. The Advanced Resource Factory will show an error if you attempt its use.

`RT_ORB_Loader`

Typically, the following options are set via the service configurator (svc.conf) file. The following line in the svc.conf file (all in one line)
static RT_ORB_Loader "[list of options]"
would load all the options listed within "".

Option Description

-ORBSchedPolicy policy Specify the scheduling policy used for the priority mapping computations and to specify the scheduling policy used when creating RTCORBA threads. Priority mappings map the CORBA priority range (from 0 to 32767) into the native OS priority range, but in some operating systems the range depends on the scheduling policy used. Valid values are SCHED_OTHER, SCHED_FIFO and SCHED_RR. Defaults to SCHED_OTHER. Note that in some operating systems some of the scheduling policies require super user privileges.

-ORBScopePolicy scope Specify the scheduling scope used when creating RTCORBA threads. Valid values are: PROCESS and SYSTEM. Defaults to PROCESS.

-ORBPriorityMapping mapping_type Select the priority mapping to use. There are three priority mappings provided by TAO: the linear mapping maps between the CORBA range of priorities and the native range of priorities; the direct mapping maps CORBA priorities directly to native priorities; and the continuous maps the first n CORBA priorities to the range of native priorities, where n is the number of native priorities. Defaults to direct. Note that continuous was previously referred to as direct.

Option	Description
`-ORBSchedPolicy` policy	Specify the scheduling policy used for the priority mapping computations and to specify the scheduling policy used when creating RTCORBA threads. Priority mappings map the CORBA priority range (from 0 to 32767) into the native OS priority range, but in some operating systems the range depends on the scheduling policy used. Valid values are SCHED_OTHER, SCHED_FIFO and SCHED_RR. Defaults to SCHED_OTHER. Note that in some operating systems some of the scheduling policies require super user privileges.
`-ORBScopePolicy` scope	Specify the scheduling scope used when creating RTCORBA threads. Valid values are: PROCESS and SYSTEM. Defaults to PROCESS.
`-ORBPriorityMapping` mapping_type	Select the priority mapping to use. There are three priority mappings provided by TAO: the linear mapping maps between the CORBA range of priorities and the native range of priorities; the direct mapping maps CORBA priorities directly to native priorities; and the continuous maps the first n CORBA priorities to the range of native priorities, where n is the number of native priorities. Defaults to direct. Note that continuous was previously referred to as direct.

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