IBM pSeries manual LoadLeveler daemons, Reducing the number of daemons running, Reducing logging

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

4.2.2Reducing 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

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