HP-UX TN3270 Administration Guide

Using Shared Memory and Semaphores

Tuning System Parameters

Appendix B74

Tuning System Parameters

Normally, the default values for these parameters are suitable for typical

TN3270 conﬁgurations. In some cases, it may be necessary to tune some

of these parameters. Tuning should only be done once TN3270 has been

successfully installed and started using the defaults. The parameters

should be set to large enough values to accommodate both the TN3270

requirements and the requirements of any other programs on the

system.

If you need to change any of these values, refer to your HP-UX

documentation for information about how to set them. Following are the

tuning parameters and their recommended values:

SHMMNI 1 + (number of concurrent copies of the TN3270

emulation program) + (total number of sessions

conﬁgured for HLLAPI)

SEMMNI (2 x number of concurrent copies of the TN3270

emulation) + (total number of sessions conﬁgured for

HLLAPI)

SEMMNS (2 x number of concurrent copies of the TN3270

emulation program) + (2 x total number of sessions

conﬁgured for HLLAPI)

SEMMAP Half the value of SEMMNS

SEMMNU (2 x number of concurrent copies of the TN3270

emulation program) + (total number of sessions

conﬁgured for HLLAPI)

SHMSEG 2 + (maximum number of sessions conﬁgured for

HLLAPI for a single user)

NOTE You can run more than one TN3270 emulation program at a time using

different HLLAPI session identiﬁers, and therefore, can have more

HLLAPI sessions conﬁgured than a single emulation program can

support. These parameters must be large enough to support all of these

sessions, even if you do not access all of them from a single HLLAPI

application.