IV36801: USE OF LARGE PAGES BY DEFAULT ON LINUX AND Z/OS

APAR status

• Closed as program error.

Error description

• Error Message: N/A
  .
  Stack Trace: N/A
  .
  

Local fix

Problem summary

• On certain platforms and processors, the JVM now starts with
  large pages enabled by default for both the JIT code cache and
  the Java object heap, instead of the default operating system
  page size.
  On z/OS, the JVM uses 1M pageable large pages, when running on
  the IBM zEnterprise EC12 with the Flash Express feature (#0402),
  z/OS V1.13 with APAR OA41307, and the z/OS V1.13 Remote Storage
  Manager Enablement Offering web deliverable.
  Note: PAGESCM=ALL <HAT>00 NONE in the IEASYSxx parmlib member
  controls 1M pageable large pages for the entire LPAR. ALL is the
  default.
  The following sizes apply to Linux:
      Linux on x86 and AMD64/EM64T: 2 MB large pages
      Linux on System z: 1 MB large pages
  Note: These changes do not apply to Linux on IBM POWER?
  platforms.
  If the operating system is not configured for the large page
  size, or if the correct hardware is not available, the JVM uses
  the default operating system page size instead.
  You can configure the large page size using the -Xlp command.
  For more information about the -Xlp command, see JVM
  command-line options:
  http://publib.boulder.ibm.com/infocenter/java7sdk/v7r0/index.jsp
  ?topic=%2Fcom.ibm.java.zos.70.doc%2Fdiag%2Fappendixes%2Fcmdline%
  2Fcommands_jvm.html.
  Please refer to technote:
    http://www-01.ibm.com/support/docview.wss?uid=swg21625018
  (Java 7 SR4)
  

Problem conclusion

• This defect will be fixed in:
  7.0.0 SR4
  .
  N/A
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  J9 COMMON CODE

• Fixed component ID

  620700127

Applicable component levels

• R260 PSY

     UP