In an highly loaded system, LLT threads might not be able to run because of relatively low priority settings. This situation may result in heartbeat failures across cluster nodes.

You can modify the priorities for the timer and service threads by configuring kernel tunables in the file /etc/llt.conf.

Following is a sample llt.conf file:

llt_maxnids=32
llt_maxports=32
llt_nominpad=0
llt_basetimer=50000
llt_thread_pri=40

Table: Priorities for LLT threads for AIX depicts the priorities for LLT threads for AIX.

Note that the priorities must lie within the priority range. If you specify a priority outside the range, LLT resets it to a value within the range.