IBM pSeries - Manual (Page 17)

pshpstuningguidewp040105.doc Page 17
4.2 LoadLeveler daemons
The LoadLeveler® daemons are needed for MPI applications using HPS. However, you can
lower the impact on a parallel application by changing the default settings for these daemons.
You can lower the impact of the LoadLeveler daemons by:
•
Reducing the number of daemons running
•
Reducing daemon communication or placing daemons on a switch
•
Reducing logging
4.2.1 Reducing the number of daemons running
Stop the keyboard daemon
On LoadL_config:
# Specify whether to start the keyboard daemon
X_RUNS_HERE = False
Allow only a few public schedd to run for submitting jobs or POE
On LoadL_config:
LOCAL_CONFIG = $(tilde)/LoadL_config.local.$(hostname)
On LoadL_config.local.plainnode:
SCHEDD_RUNS_HERE = False
On LoadL_config.local.scheddnode:
SCHEDD_RUNS_HERE = True
On LoadL_admin for schedd node to make public:
node_name.xxx.xxx.xxx: type = machine
alias = node_name1.xxx.xxx.xxx node_name2.xxx.xxx.xxx
schedd_host=true
4.2.2 Reducing daemon communication and placing
daemons on a switch
On LoadL_config:
# Set longer to reduce daemon messages. This will slow response to failures.
POLLING_FREQUENCY = 600
POLLS_PER_UPDATE = 1
MACHINE_UPDATE_INTERVAL = 1200
Use the switch traffic for daemon communication.
4.2.3 Reducing logging
On LoadL_config:
# reduce LoadLeveler activity to minimum. Warning: You will not be notified of failures.
NEGOTIATOR_DEBUG = -D_ALWAYS
NEGOTIATOR_DEBUG = -D_ALWAYS
STARTD_DEBUG = -D_ALWAYS