Configuring your environment
Although some configuration options must be set before you run your Java™ application, many options are configured when you launch the runtime environment from the command line. Configuration options that must be set before you start your application include operating system resources and hardware components that can be exploited by applications.
While some configuration options apply to all platforms, a number are platform-specific, particularly when the option relates to hardware or operating system resources. Some features have additional software dependencies.
- To ensure that your operating system allocates sufficient resources for your application, set suitable values for ulimits (AIX® and Linux®), BPXPRM parameters (z/OS®), and Language Environment runtime options (z/OS). If your application allocates a large amount of memory and frequently accesses that memory, you might want to enable large page support on your system. If you are running your application on an IBM® Power® system, you can use the com.ibm.lang.management API to take advantage of DLPAR capabilities for the dynamic movement of memory, CPU capacity, and I/O interfaces between LPARs. For more information about all of these options, see Configuring your system in the OpenJ9 user documentation (except for information that is specific to 32-bit or 31-bit systems, which is in the sub-topics).
- To configure your system to use Graphics Processing Units (GPU), see GPU system requirements.
- To configure your system to use RDMA network infrastructure by using Java Sockets over RDMA (JSOR), see JSOR system requirements and supported APIs (Linux only) or Shared Memory Communications via Remote Direct Memory Access (z/OS only).
- To configure your system to use RDMA network infrastructure by writing applications that use the jVerbs library, see jVerbs application system and runtime requirements (Linux only).
- To configure your system to use z/Enterprise data compression, see zEnterprise Data Compression (z/OS only).
- To configure your system to use other hardware compression acceleration devices, see Enabling hardware compression acceleration (AIX, Linux only) .