Oracle Business Process Execution Language (BPEL) Process Manager provides several property settings that can be configured to optimize performance at the composite, fabric, application and server levels. This chapter describes these property settings and provides recommendations on how to use them.
This chapter contains the following sections:
BPEL is the standard for assembling a set of discrete services into an end-to-end process flow, radically reducing the cost and complexity of process integration initiatives. Oracle BPEL Process Manager offers a comprehensive and easy-to-use infrastructure for creating, deploying and managing BPEL business processes.
For more information, see "Configuring BPEL Process Service Components and Engines" in Oracle Fusion Middleware Administrator's Guide for Oracle SOA Suite and "Using the BPEL Process Service Component" in Oracle Fusion Middleware Developer's Guide for Oracle SOA Suite.
This section describes the basic BPEL Process Manager performance tuning properties that are configured either through WLST or Oracle Enterprise Manager. To modify properties through WLST, see Section 11.3, "Modifying SOA Configuration Parameters".
Note:
The configuration examples and recommended settings described in this chapter are for illustrative purposes only. Consult your own use case scenarios to determine which configuration options can provide performance improvements.When the dispatcher must schedule a dispatch message for execution, it can enqueue the message into a thread pool. Each dispatch set can contain a thread pool (java.util.concurrent.ThreadPoolExecutor). The BPEL thread pool implementation notifies the threads when a message has been enqueued and ensures the appropriate number of threads are instantiated in the pool.
The following thread properties can be tuned:
Note:
dspMinThreads, dspMaxThreads and dspInvokeAllocRatio configuration properties are deprecated in Oracle 11g. In addition, the invoke threads have their own pool in Oracle 11g so the dspInvokeAllocRatio is no longer required.The dspInvokeThreads property specifies the total number of threads allocated to process invocation dispatcher messages. Invocation dispatcher messages are generated for each payload received and are meant to instantiate a new instance. If the majority of requests processed by the engine are instance invocations (as opposed to instance callbacks), greater performance may be achieved by increasing the number of invocation threads. Higher thread counts may cause greater CPU utilization due to higher context switching costs.
The minimum number of threads for this thread pool is 1 and it cannot be set to 0 a or negative number.
The default value is 20 threads. Any value less than 1 thread is changed to the default.
The dspEngineThreads property specifies the total number of threads allocated to process engine dispatcher messages. Engine dispatcher messages are generated whenever an activity must be processed asynchronously. If the majority of processes deployed are durable with a large number of dehydration points (mid-process receive, onMessage, onAlarm, and wait activities), greater performance may be achieved by increasing the number of engine threads. Note that higher thread counts can cause greater CPU utilization due to higher context switching costs.
The minimum number of threads for this thread pool is 1 and it cannot be set to 0 a or negative number.
The default value is 30 threads. Any value less than 1 thread is changed to the default.
The dspSystemThreads property specifies the total number of threads allocated to process system dispatcher messages. System dispatcher messages are general clean-up tasks that are typically processed quickly by the server (for example, releasing stateful message beans back to the pool). Typically, only a small number of threads are required to handle the number of system dispatch messages generated during run time.
The minimum number of threads for this thread pool is 1 and it cannot be set to 0 a or negative number.
The default value is 2. Any value less than 1 thread is changed to the default.
The dspMaxRequestDepth property sets the maximum number of in-memory activities to process within the same request. After processing an activity request, Oracle BPEL Process Manager attempts to process as many subsequent activities as possible without jeopardizing the validity of the request. Once the activity processing chain has reached this depth, the instance is dehydrated and the next activity is performed in a separate transaction.
If the request depth is too large, the total request time can exceed the application server transaction time out limit.This process is applicable to durable processes.
The default value is 600 activities.
Note:
Note that the minimum number of threads for each thread pool is 1. dsp*Threads can not be set to 0 or negative.The auditLevel property sets the audit trail logging level. This configuration property is applicable to both durable and transient processes. This property controls the amount of audit events that are logged by a process. Audit events result in more database inserts into the audit_trail table which may impact performance. Audit information is used only for viewing the state of the process from Oracle Enterprise Manager Console.
Use the Off value if you do not want to store any audit information. Always choose the audit level according to your business requirements and use cases. For more information on setting the audit level, see "Understanding the Order of Precedence for Audit Level Settings" in Oracle Fusion Middleware Administrator's Guide for Oracle SOA Suite.
| Value | Description |
|---|---|
| Inherit | Inherits the audit level from infrastructure level. |
| Off | No audit events (activity execution information) are persisted and no logging is performed; this can result in a slight performance boost for processing instances. |
| Minimal | All events are logged; however, no audit details (variable content) are logged. |
| Error | Logs only serious problems that require immediate attention from the administrator and are not caused by a bug in the product. Using this level can help performance. |
| Production | All events are logged. The audit details for assign activities are not logged; the details for all other activities are logged. |
| Development | All events are logged; all audit details for all activities are logged. |
The oneWayDeliveryPolicy is from the Oracle 10g configuration property deliveryPersistencePolicy.
The new configuration property name is bpel.config.oneWayDeliveryPolicy.
WARNING:
If you set this property to async.cache and your system fails, you may lose messages. For more information, refer to the Oracle BPEL Process Manager Administrator's Guide.
The oneWayDeliveryPolicy property controls database persistence of messages entering Oracle BPEL Server. By default, incoming requests are saved in the delivery service database table dlv_message. These requests are later acquired by Oracle BPEL Server worker threads and delivered to the targeted BPEL process. This property persists delivery messages and is applicable to durable processes.
If you set the oneWayDeliveryPolicy property to async.cache and your system fails, you may lose messages. In addition, the system can become overloaded (messages become backlogged in the scheduled queue) and you may receive out-of-memory errors. Consult your own use case scenarios to determine if this setting is appropriate.
One-way invocation messages are stored in the delivery cache until delivered. If the rate at which one-way messages arrive is much higher than the rate at which Oracle BPEL Server delivers them, or if the server fails, messages may be lost.
| Value | Description |
|---|---|
| async.persist (Default) | Delivery messages are persisted in the database. With this setting, reliability is obtained with some performance impact on the database. In some cases, overall system performance can be impacted. |
| async.cache | Incoming delivery messages are kept only in the in-memory cache. If performance is preferred over reliability, this setting should be considered. |
| sync | Directs Oracle BPEL Server to bypass the scheduling of messages in the invoke queue, and invokes the BPEL instance synchronously. In some cases this setting can improve database performance. |
The StatsLastN property sets the size of the most-recently processed request list. After each request is finished, statistics for the request are kept in a request list. A value less than or equal to 0 disables statistics gathering. To optimize performance, consider disabling statistics collection if you do not need them.
This property is applicable to both durable and transient processes.
The default value is -1.
The auditdetailthreshold property sets the maximum size (in kilobytes) of an audit trail details string before it is stored separately from the audit trail. If an audit trail details string is larger than the threshold setting, it is not immediately loaded when the audit trail is initially retrieved; a link is displayed with the size of the details string. Strings larger than the threshold setting are stored in the audit_details table, instead of the audit_trail table.
The details string typically contains the contents of a BPEL variable. In cases where the variable is very large, performance can be severely impacted by logging it to the audit trail.
The default value is 50000 (50 kilobytes).
The largedocumentthreshold property sets the large XML document persistence threshold. This is the maximum size (in kilobytes) of a BPEL variable before it is stored in a separate location from the rest of the instance scope data.
This property is applicable to both durable and transient processes.
Large XML documents impact the performance of the entire Oracle BPEL Server if they are constantly read in and written out whenever processing on an instance must be performed.
The default value is 10000 (100 kilobytes).
The validateXML property validates incoming and outgoing XML documents. If set to True, the Oracle BPEL Process Manager applies schema validation for incoming and outgoing XML documents.
This property is applicable to both durable and transient processes.
The default value is False.
The SyncMaxWaitTime property sets the maximum time the process result receiver waits for a result before returning. Results from asynchronous BPEL processes are retrieved synchronously by a receiver that waits for a result from Oracle BPEL Server.
This property is applicable to transient processes.
The default value is 45 seconds.
The InstanceKeyBlockSize property controls the instance ID range size. Oracle BPEL Server creates instance keys (a range of process instance IDs) in batches using the value specified. After creating this range of in-memory IDs, the next range is updated and saved in the ci_id_range table.
For example, if instanceKeyBlockSize is set to 100, Oracle BPEL Server creates a range of instance keys in-memory (100 keys, which are later inserted into the cube_instance table as cikey). To maintain optimal performance, ensure that the block size is larger than the number of updates to the ci_id_range table.
The default value is 10000.
This section lists the config properties of some sections of the deployment descriptor. For each configuration property parameter, a description is given, as well as the expected behavior of the engine when it is changed.
All the properties set in this section affect the behavior of the component containing the BPEL process only. Each BPEL process can be created as a component of a composite. These properties are modified through WLST.
The following component properties can be tuned for performance:
This property indicates to Oracle BPEL Server that this process is a transient process and dehydration of the instance is not required. When set to True, the completionPersistPolicy is used to determine persistence behavior. This property can only be set to True for transient processes or processes that do not contain any dehydration points such as receive, wait, onMessage and onAlarm activities. The inMemoryOptimization property is set at the BPEL component level. When set to False, dehydration is disabled which can improve performance in some use cases.
Values:
This property has the following values:
False (default): instances are persisted completely and recorded in the dehydration store database.
True: The completionPersist policy is used to determine persistence behavior. See Section 13.3.1.2.
This property configures how the instance data is saved. It can only be set at the BPEL component level. The completionPersistPolicy property can only be used when inMemoryOptimization is set to be True (transient processes). Note that this parameter may affect database growth and throughput (due to reduced I/O).
| Value | Description |
|---|---|
| On (default) | The completed instance is saved normally |
| Deferred | The completed instance is saved, but with a different thread and in another transaction. |
| Faulted | Only the faulted instances are saved. |
| Off | No instances of this process are saved. |
You can dynamically configure a partner link at runtime in BPEL. This is useful for scenarios in which the target service that BPEL wants to invoke is not known until runtime. The following Partner Link properties can be tuned for performance:
An idempotent activity is an activity that can be retried (for example, an assign activity or an invoke activity). Oracle BPEL Server saves the instance after a nonidempotent activity. This property is applicable to both durable and transient processes.
Values:
This property has the following values:
False: Activity is dehydrated immediately after execution and recorded in the dehydration store. When idempotent is set to False, it provides better failover protection, but may impact performance if the BPEL process accesses the dehydration store frequently.
True (default): If Oracle BPEL Server fails, it performs the activity again after restarting. This is because the server does not dehydrate immediately after the invoke and no record exists that the activity executed. Some examples of where this property can be set to True are: read-only services (for example, CreditRatingService) or local EJB/WSIF invocations that share the instance's transaction.
By default, Oracle BPEL Process Manager executes in a single thread, executing the branches sequentially instead of in parallel. When this property is set to True, the process manager creates a new thread to perform each branch's invoke activity in parallel. This property is applicable to both durable and transient processes.
Consider setting this property to True if you have invoke activities in multiple flow or flow n branches. This is especially effective if the parallel invoke activities are two-way, but some benefits can be realized for parallel one-way invokes as well.
Values:
This property has the following values:
True: Oracle BPEL Server spawns a new thread to execute the invocation.
False (default): Oracle BPEL Server executes the invoke activity in the single process thread.
Enables message boundary validation. Note that additional validation can impact performance by consuming extra CPU and memory resources.
Values:
True: When set to True the engine validates the XML message against the XML schema during <receive> and <invoke> for this partner link. If the XML message is invalid then bpelx:invalidVariables run time BPEL Fault is thrown. This overrides the domain level validateXML property.
False (default): Disables XML validation.
Instance data occupies space in Oracle BPEL Process Manager schema tables. Data growth from auditing and dehydration can have a significant impact on database performance and throughput. See Section 13.2.2, "Audit Level" for audit configuration and Section 13.3.1.1, "inMemoryOptimization" for dehydration configuration. The table below describes the tables that are impacted by instance data growth. A brief description is provided of each table.
Table 13-1 Oracle BPEL Process Manager Tables Impacted by Instance Data Growth
| Table Name | Table Description |
|---|---|
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Stores the audit trail for instances. The audit trail viewed in Oracle BPEL Control is created from an XML document. As an instance is processed, each activity writes events to the audit trail as XML. |
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Stores audit details that can be logged through the API. Activities such as an assign activity log the variables as audit details by default. Audit details are separated from the |
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Stores process instance metadata (for example, the instance creation date, current state, title, and process identifier) |
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Stores the scope data for an instance (for example, all variables declared in the BPEL flow and some internal objects that help route logic throughout the flow). |
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Stores incoming (invocation) and callback messages upon receipt. This table only stores the metadata for a message (for example, current state, process identifier, and receive date). |
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Stores delivery subscriptions for an instance. Whenever an instance expects a message from a partner (for example, the receive or onMessage activity) a subscription is written out for that specific receive activity. |
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Stores cube instance references to data stored in the |
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Stores references to |
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Stores tasks created for an instance. The TaskManager process keeps its current state in this table. |
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Stores activities created by an instance. All activities in a BPEL flow have a |
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Stores all large objects in the system (for example, |
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Stores headers and properties information. |