docs/administration-guide/src/main/asciidoc/threadpools.adoc - glassfish - Git at Google

 type=page
 status=published
 title=Administering Thread Pools
 next=webapps.html
 prev=jvm.html
 ~~~~~~

 = Administering Thread Pools

 [[GSADG00008]][[abluc]]


 [[administering-thread-pools]]
 == 5 Administering Thread Pools

 This chapter provides procedures for administering thread pools in the
 {productName} 7 environment by using the
 `asadmin` command-line utility.

 The following topics are addressed here:

 * link:#ggjyv[About Thread Pools]
 * link:#ablud[Configuring Thread Pools]

 Instructions for accomplishing these tasks by using the Administration
 Console are contained in the Administration Console online help.

 [[ggjyv]][[GSADG00546]][[about-thread-pools]]

 === About Thread Pools

 The Virtual Machine for the Java platform (Java Virtual Machine) or JVM
 machine) can support many threads of execution simultaneously. To help
 performance, {productName} maintains one or more thread pools. It is
 possible to assign specific thread pools to connector modules, to
 network listeners, or to the Object Request Broker (ORB).

 One thread pool can serve multiple connector modules and enterprise
 beans. Request threads handle user requests for application components.
 When {productName} receives a request, it assigns the request to a
 free thread from the thread pool. The thread executes the client's
 requests and returns results. For example, if the request needs to use a
 system resource that is currently busy, the thread waits until that
 resource is free before allowing the request to use that resource.

 [[ablud]][[GSADG00547]][[configuring-thread-pools]]

 === Configuring Thread Pools

 You can specify the minimum and maximum number of threads that are
 reserved for requests from applications. The thread pool is dynamically
 adjusted between these two values.

 The following topics are addressed here:

 * link:#ggkwj[To Create a Thread Pool]
 * link:#giuff[To List Thread Pools]
 * link:#ggkyc[To Update a Thread Pool]
 * link:#ggkwy[To Delete a Thread Pool]

 [[ggkwj]][[GSADG00366]][[to-create-a-thread-pool]]

 ==== To Create a Thread Pool

 Use the `create-threadpool` subcommand in remote mode to create a thread
 pool.

 The minimum thread pool size that is specified signals the server to
 allocate at least that many threads in reserve for application requests.
 That number is increased up to the maximum thread pool size that is
 specified. Increasing the number of threads available to a process
 allows the process to respond to more application requests
 simultaneously.

 If one resource adapter or application occupies all the {productName}
 threads, thread starvation might occur. You can avoid this by dividing
 the {productName} threads into different thread pools.

 1. Ensure that the server is running. Remote subcommands require a running server.
 2. Create a new thread pool by using the
 link:reference-manual/create-threadpool.html#GSRFM00060[`create-threadpool`] subcommand.
 +
 Information about options for the subcommand is included in this help
 page.
 3. To apply your changes, restart {productName}.
 +
 See link:domains.html#ginqj[To Restart a Domain].
 +

 [NOTE]
 ====
 Restart is not necessary for thread pools used by the web container.
 ====


 [[GSADG00162]][[giuez]]
 Example 5-1 Creating a Thread Pool

 This example creates `threadpool-l`.

 [source]
 ----
 asadmin> create-threadpool --maxthreadpoolsize 100
 --minthreadpoolsize 20 --idletimeout 2 --workqueues 100 threadpool-1
 Command create-threadpool executed successfully
 ----

 [[GSADG853]]

 See Also

 You can also view the full syntax and options of the subcommand by
 typing `asadmin help create-threadpool` at the command line.

 [[giuff]][[GSADG00367]][[to-list-thread-pools]]

 ==== To List Thread Pools

 Use the `list-threadpools` subcommand in remote mode to list the
 existing thread pools.

 1. Ensure that the server is running. Remote subcommands require a running server.
 2. List the existing thread pools by using the
 link:reference-manual/list-threadpools.html#GSRFM00204[`list-threadpools`] subcommand.

 [[GSADG00163]][[giugs]]
 Example 5-2 Listing Thread Pools

 This example lists the existing thread pools.

 [source]
 ----
 asadmin> list-threadpools
 threadpool-1
 Command list-threadpools executed successfully
 ----

 [[GSADG854]]

 See Also

 You can also view the full syntax and options of the subcommand by
 typing `asadmin help list-threadpools` at the command line.

 [[ggkyc]][[GSADG00368]][[to-update-a-thread-pool]]

 ==== To Update a Thread Pool

 Use the `set` subcommand to update the values for a specified thread
 pool.

 1. List the existing thread pools by using the
 link:reference-manual/list-threadpools.html#GSRFM00204[`list-threadpools`] subcommand.
 2. Modify the values for a thread pool by using the
 link:reference-manual/set.html#GSRFM00226[`set`] subcommand.
 +
 The thread pool is identified by its dotted name.
 3. To apply your changes, restart {productName}.
 +
 See link:domains.html#ginqj[To Restart a Domain].
 +

 [NOTE]
 ====
 Restart is not necessary for thread pools used by the web container.
 ====


 [[GSADG00164]][[giuhc]]
 Example 5-3 Updating a Thread Pool

 This example sets the `max-thread-pool-size` from its previous value to
 8. [source]
 ----
 asadmin> set server.thread-pools.thread-pool.http-thread-pool.max-thread-pool-size=8
 Command set executed successfully
 ----

 [[GSADG855]]

 See Also

 You can also view the full syntax and options of the subcommand by
 typing `asadmin help set` at the command line.

 [[ggkwy]][[GSADG00369]][[to-delete-a-thread-pool]]

 ==== To Delete a Thread Pool

 Use the `delete-threadpool` subcommand in remote mode to delete an
 existing thread pool. Deleting a thread pool will fail if that pool is
 referenced by a network listener.

 1. Ensure that the server is running. Remote subcommands require a running server.
 2. List the existing thread pools by using the
 link:reference-manual/list-threadpools.html#GSRFM00204[`list-threadpools`] subcommand.
 3. Delete the specified thread pool by using the
 link:reference-manual/delete-threadpool.html#GSRFM00111[`delete-threadpool`] subcommand.
 4. To apply your changes, restart {productName}.
 +
 See link:domains.html#ginqj[To Restart a Domain].
 +

 [NOTE]
 ====
 Restart is not necessary for thread pools used by the web container.
 ====


 [[GSADG00165]][[giugt]]
 Example 5-4 Deleting a Thread Pool

 This example deletes `threadpool-1`.

 [source]
 ----
 asadmin> delete-threadpool threadpool-1
 Command delete-threadpool executed successfully
 ----

 [[GSADG856]]

 See Also

 You can also view the full syntax and options of the subcommand by
 typing `asadmin help delete-threadpool` at the command line.
	type=page
	status=published
	title=Administering Thread Pools
	next=webapps.html
	prev=jvm.html
	~~~~~~

	= Administering Thread Pools

	[[GSADG00008]][[abluc]]


	[[administering-thread-pools]]
	== 5 Administering Thread Pools

	This chapter provides procedures for administering thread pools in the
	{productName} 7 environment by using the
	`asadmin` command-line utility.

	The following topics are addressed here:

	* link:#ggjyv[About Thread Pools]
	* link:#ablud[Configuring Thread Pools]

	Instructions for accomplishing these tasks by using the Administration
	Console are contained in the Administration Console online help.

	[[ggjyv]][[GSADG00546]][[about-thread-pools]]

	=== About Thread Pools

	The Virtual Machine for the Java platform (Java Virtual Machine) or JVM
	machine) can support many threads of execution simultaneously. To help
	performance, {productName} maintains one or more thread pools. It is
	possible to assign specific thread pools to connector modules, to
	network listeners, or to the Object Request Broker (ORB).

	One thread pool can serve multiple connector modules and enterprise
	beans. Request threads handle user requests for application components.
	When {productName} receives a request, it assigns the request to a
	free thread from the thread pool. The thread executes the client's
	requests and returns results. For example, if the request needs to use a
	system resource that is currently busy, the thread waits until that
	resource is free before allowing the request to use that resource.

	[[ablud]][[GSADG00547]][[configuring-thread-pools]]

	=== Configuring Thread Pools

	You can specify the minimum and maximum number of threads that are
	reserved for requests from applications. The thread pool is dynamically
	adjusted between these two values.

	The following topics are addressed here:

	* link:#ggkwj[To Create a Thread Pool]
	* link:#giuff[To List Thread Pools]
	* link:#ggkyc[To Update a Thread Pool]
	* link:#ggkwy[To Delete a Thread Pool]

	[[ggkwj]][[GSADG00366]][[to-create-a-thread-pool]]

	==== To Create a Thread Pool

	Use the `create-threadpool` subcommand in remote mode to create a thread
	pool.

	The minimum thread pool size that is specified signals the server to
	allocate at least that many threads in reserve for application requests.
	That number is increased up to the maximum thread pool size that is
	specified. Increasing the number of threads available to a process
	allows the process to respond to more application requests
	simultaneously.

	If one resource adapter or application occupies all the {productName}
	threads, thread starvation might occur. You can avoid this by dividing
	the {productName} threads into different thread pools.

	1. Ensure that the server is running. Remote subcommands require a running server.
	2. Create a new thread pool by using the
	link:reference-manual/create-threadpool.html#GSRFM00060[`create-threadpool`] subcommand.
	+
	Information about options for the subcommand is included in this help
	page.
	3. To apply your changes, restart {productName}.
	+
	See link:domains.html#ginqj[To Restart a Domain].
	+

	[NOTE]
	====
	Restart is not necessary for thread pools used by the web container.
	====


	[[GSADG00162]][[giuez]]
	Example 5-1 Creating a Thread Pool

	This example creates `threadpool-l`.

	[source]
	----
	asadmin> create-threadpool --maxthreadpoolsize 100
	--minthreadpoolsize 20 --idletimeout 2 --workqueues 100 threadpool-1
	Command create-threadpool executed successfully
	----

	[[GSADG853]]

	See Also

	You can also view the full syntax and options of the subcommand by
	typing `asadmin help create-threadpool` at the command line.

	[[giuff]][[GSADG00367]][[to-list-thread-pools]]

	==== To List Thread Pools

	Use the `list-threadpools` subcommand in remote mode to list the
	existing thread pools.

	1. Ensure that the server is running. Remote subcommands require a running server.
	2. List the existing thread pools by using the
	link:reference-manual/list-threadpools.html#GSRFM00204[`list-threadpools`] subcommand.

	[[GSADG00163]][[giugs]]
	Example 5-2 Listing Thread Pools

	This example lists the existing thread pools.

	[source]
	----
	asadmin> list-threadpools
	threadpool-1
	Command list-threadpools executed successfully
	----

	[[GSADG854]]

	See Also

	You can also view the full syntax and options of the subcommand by
	typing `asadmin help list-threadpools` at the command line.

	[[ggkyc]][[GSADG00368]][[to-update-a-thread-pool]]

	==== To Update a Thread Pool

	Use the `set` subcommand to update the values for a specified thread
	pool.

	1. List the existing thread pools by using the
	link:reference-manual/list-threadpools.html#GSRFM00204[`list-threadpools`] subcommand.
	2. Modify the values for a thread pool by using the
	link:reference-manual/set.html#GSRFM00226[`set`] subcommand.
	+
	The thread pool is identified by its dotted name.
	3. To apply your changes, restart {productName}.
	+
	See link:domains.html#ginqj[To Restart a Domain].
	+

	[NOTE]
	====
	Restart is not necessary for thread pools used by the web container.
	====


	[[GSADG00164]][[giuhc]]
	Example 5-3 Updating a Thread Pool

	This example sets the `max-thread-pool-size` from its previous value to
	8. [source]
	----
	asadmin> set server.thread-pools.thread-pool.http-thread-pool.max-thread-pool-size=8
	Command set executed successfully
	----

	[[GSADG855]]

	See Also

	You can also view the full syntax and options of the subcommand by
	typing `asadmin help set` at the command line.

	[[ggkwy]][[GSADG00369]][[to-delete-a-thread-pool]]

	==== To Delete a Thread Pool

	Use the `delete-threadpool` subcommand in remote mode to delete an
	existing thread pool. Deleting a thread pool will fail if that pool is
	referenced by a network listener.

	1. Ensure that the server is running. Remote subcommands require a running server.
	2. List the existing thread pools by using the
	link:reference-manual/list-threadpools.html#GSRFM00204[`list-threadpools`] subcommand.
	3. Delete the specified thread pool by using the
	link:reference-manual/delete-threadpool.html#GSRFM00111[`delete-threadpool`] subcommand.
	4. To apply your changes, restart {productName}.
	+
	See link:domains.html#ginqj[To Restart a Domain].
	+

	[NOTE]
	====
	Restart is not necessary for thread pools used by the web container.
	====


	[[GSADG00165]][[giugt]]
	Example 5-4 Deleting a Thread Pool

	This example deletes `threadpool-1`.

	[source]
	----
	asadmin> delete-threadpool threadpool-1
	Command delete-threadpool executed successfully
	----

	[[GSADG856]]

	See Also

	You can also view the full syntax and options of the subcommand by
	typing `asadmin help delete-threadpool` at the command line.