What's New?

• New Features
  • Added the ability to restrict a task to agents running a specific OS by adding OSPlatform to CommonResources and adding OSPlatform enumeration. See getTaskPreconditions() for an example using CommonResources.

• Minor bug fixes and improvements.

• Minimum Java version updated to Java 8.

• Updated to work with Ansys licensing.

• Updated for version 2.2 of the STK Parallel Computing Server Coordinator and Agent services, which are now available on Linux.

• Updated for version 2.1 of the STK Parallel Computing Server Coordinator and Agent services.

• The product formerly known as STK Scalability Extension has been renamed to STK Parallel Computing Server.

• New Features
  • Added the ability to specify a task's estimated memory usage (TaskProperties.ESTIMATED_MEMORY_USAGE_FOR_TASK), which is taken into account to honor the Agent's Estimated Memory Budget (EstimatedMemoryBudget). This facilitates worker process assignments when using tasks that require a large amount of memory. See the discussion section of the help topic Constrain the amount of resources required for a task to be scheduled for more details.

• Updated for Coordinator and Agent services 1.6.

• The default installation location has been changed from C:\Program Files (x86) to C:\Program Files.

• Improvements
  • Removed the IDisposable interface in favor of Closeable . This enables the try-with-resources statement across the API.
  • Deprecated the dispose() method; use close() instead or the try-with-resources statement.
  • Log files and the communication protocol used between the clients, coordinator, and agents have been changed to use UTF-8 encoding. This provides better support for extended characters and is backwards compatible with the previously used ASCII encoding.
  • Some compatibility exceptions have been replaced by their direct equivalent. These should not have any impact on existing code using the API as these exceptions were mostly internal. However, if your code used these exceptions, it needs to be updated with the following mapping:
    • IllegalStateException -> NullPointerException
    • ArgumentException -> IllegalArgumentException
    • ArgumentOutOfRangeException -> IllegalArgumentException
    • RuntimeIllegalAccessException -> UnsupportedOperationsException
    • ArgumentNullException -> NullPointerException
    • KeyNotFoundException -> IllegalArgumentException
  • A few compatibility classes (StringHelper, MapHelper, and IntHelper) have been removed and the code updated to use their direct Java equivalent. These classes were mostly internal, but if you used them in your code, it needs to be updated to use the equivalent classes and methods directly from Java.
• Bug Fixes
  • Fixed an issue where the listener added through the Job.addJobCompletedListener() method would not be invoked before Job.WaitUntilDone() exited.

• New Features
  • Added the option for a Coordinator using secure connections (TLS 1.2) to require clients to provide security certificates for validation (mutual SSL). Read the updated Connect to the Coordinator with TLS1.2 topic for details.
  • Added a new getIsFinishedTaskStatus() property to Task to help determine which TaskStatuses are interpreted as finished.
• Improvements
  • Improved assembly serialization to minimize Large Object Heap (LOH) fragmentation.
• Bug Fixes
  • addTask() now throws an ArgumentException when trying to add the same task to a job more than once to prevent a case where a job would never finish.

• The minimum version of Java required has changed from 5 to 7.

• New Features
  • New options to secure communications between the coordinator and agents/clients using SSL (TLS v1.2) have been added. Read the new Connect to the Coordinator with TLS1.2 topic for details.

• New Features
  • New options to control the lifetime of host processes have been added. Hosts are recyclable after any one of a variety of time, memory, or job-based conditions have been satisfied. The Agent Tray Application has a new Host Recycling panel to set values for these options. The values set in the Agent Tray Application UI will be overridden if a submitted job's TaskEnvironment's HostRecycleSettings have been set programmatically.
• Improvements
  • Reduced the amount of logging the external capability checkers generated in the agent log.
  • Improved capture of task standard output.
• Bug Fixes
  • Fixed a bug where running parallel coverage with tirem could cause a host to hang in rare conditions.

• The product formerly known as STK Server has been renamed to STK Scalability Extension.

• New Features
  • Clients now automatically try to reconnect to the coordinator if the network connection between the two is lost. This behavior is controlled by the new properties (CoordinatorReconnectionDelay, CoordinatorReconnectionInterval, and MaximumReconnectionAttempts) added to the ClusterJobScheduler class and exposed via a new client configuration file (ClientSettings.config).
  • Tasks have a new readable property, TaskProperties.INTERRUPTED_RETRY_ATTEMPTS, which specifies the number of times a task has been retried after its execution has been interrupted (e.g. by a terminating process).
• Improvements
  • Added a new throttling capability to the coordinator to better manage its memory usage when running jobs with high memory requirements.
  • Improved memory management when executing tasks with large payloads/results.
  • The detection of unresponsive elements in the system and their associated heartbeat messages used to rely on the local machine time and could therefore be wrongfully triggered if the local machine time was modified (e.g. manually or due to daylight savings). This logic has been reworked to no longer depend on the local machine time and is thus now immune to local machine time modifications.
  • Any non-default configuration value is now logged.
  • Added caching for the byte arrays used during message serialization to improve performance.
• Bug Fixes
  • Fixed a race condition that could result in the agent service crashing if a host repeatedly failed after finishing a task.
  • Fixed the documentation on the expected behavior when Job.RaiseEventsUsingSynchronizationContext is true (.NET API only).
  • In some cases, IJobSchedulerContext.reserveResource(java.lang.String, long) would return an exception without waiting for the resouces to be available. This has been fixed and IJobSchedulerContext.reserveResource(java.lang.String, long) will now block until the requested resources become available or the specified timeout expires.
  • Fixed spurious debug messages in the agent log relating to invalid format strings.
  • Fixed a bug where the agent service might not have retried a task when the host failed to start due to low memory conditions. In these cases the task will now be retried similarly to the other failure cases.

The first release of STK Scalability API for Java!