AIXTHREAD_SCOPE

S

Controls contention scope. S signifies system-based contention scope (1:1).

AIXTHREAD_MNRATIO

1:1

Controls the M:N ratio of number of kernel threads that must be employed to handle runnable pthreads.

AIXTHREAD_MUTEX_DEBUG

OFF

Maintains a list of active mutexes for use by the debugger.

AIXTHREAD_RWLOCK_DEBUG

OFF

Maintains a list of read-write locks for use by the debugger.

AIXTHREAD_COND_DEBUG

OFF

Maintains a list of condition variables for use by the debugger.

SPINLOOPTIME

1000

Controls the number of times to retry a busy lock before yielding to another processor.

YIELDLOOPTIME

>=n

A number greater than or equal to the number of CPUs.

Controls the number of times to yield the processor before blocking on a busy lock (only for libpthreads). Set this variable, at the minimum, to a number equal to the number of CPUs on the computer.

MALLOCOPTIONS

buckets,considersize,multiheap:4

Include in the value an integer representing the number of processors on this computer. In this case, the value 4 would be used for a four-processor computer.

LDR_CNTRL

Example values:

LOADPUBLIC@MAXDATA=0x50000000 (this value, which specifies five segments, sets a maximum process size of 1.25 GB)

LOADPUBLIC@MAXDATA=0x60000000 (this value, which specifies six segments, sets a maximum process size of 1.5 GB)

The LOADPUBLIC option directs the system loader to load all modules requested by an application into the global shared library segment. Set LDR_CNTRL in the environment of the user, or, preferably, in the shell script that launches the executable program that needs the extra memory.