System Commands
- smtctl -m on|off -w now|boot
Controls the enabling and disabling of processor simultaneous multi-threading mode.
- vmo -r -o lgpg_regions=n -o lgpg_size=16777216
Sets the size of large pages to 16M, and set the number to use, with -r, takes effect on the next IPL.
- bosboot -q
Regenerates the IPL boot to set the options specified with smtctl and vmo.
- ulimit
Controls resources allowed to be used by processes. All resource are set to unlimited, of primary importance is the "stack" and "data/heap" settings.
Environment variables set before the run:
- MEMORY_AFFINITY=MCM
Cause the OS to alloc memory "closest" to the chip that first requests it.
- MALLOCOPTIONS=POOL
Selects the OS malloc option that allocates/frees small objects very quickly.
- XLFRTEOPTS=intrinthrds=1
Causes the Fortran runtime to only use a single thread.
]]>