Enabling xplink in the runtime environment and compiling
applications with xplink enabled improves performance in z/OS® V1R2.
- For best performance, use the LPALSTxx parmlib member to ensure that LE and C++ runtimes are
loaded into LPA, as shown in the following example:
Example: sys1.parmlib(LPALSTxx):
********************************* Beginning of Data ********************
USER.LPALIB,
ISF.SISFLPA, SDSF
CEE.SCEELPA,
LANGUAGE ENVIRONMENT
CBC.SCLBDLL, C++ RUNTIME
.
.
.
******************************** End of Data ******************
- Ensure that the Language Environment® data sets, SCEERUN and SCEERUN2, are authorized to enable xplink.
For processes that run the client ORB, since they start the JVM,
must run with xplink (on). For best performance, compile applications
that use JNI services with xplink enabled. Compiling applications
with xplink enabled improves performance in z/OS V1R2.
As you move from z/OS V1R2 to z/OS V1R6
you should experience additional performance improvements when all
of the LE services calls are xplink enabled.
- Ensure that you are NOT using the following options during production:
- RPTSTG(ON)
- RPTOPTS(ON)
- HEAPCHK(ON)
- Turn LE heappools on.
If you are running a client on z/OS, setting the following: SET LEPARM='HEAPP(ON)' in a shell script, turns on LE heappools, which should improve
the performance of the client.
- Refer to Fine tuning the LE heap
Customization Note: Do not modify LE
parameters without consulting IBM® support. The LE parameters are
set internally to ensure the best possible performance of the WebSphere Application Server, which is
the main LE application running in the address space. If you need
to add or change LE parameters, make sure that you work with the IBM WebSphere support team to ensure that the
internally set parameters are not compromised. The appropriate interface
for making these changes is through the PARM=
parameter
of the EXEC PGM=BPXBATSL
statement in the startup
JCL.