How does one determine whether to bust jobs into a different pool?

I get that expert caching helps paging a shared pool by the job types, etc from a high level. But how does one determine whether or not one should bust jobs or subsystems into their own pools?
Is there then a concern that too many pools may create islands of underutilized memory?

Select
count(*) as job_count,
SUBSYSTEM,
SUBSYSTEM_LIBRARY_NAME,
JOB_TYPE,
MEMORY_POOL,
SYSTEM_POOL_ID,
POOL_NAME
from table(qsys2.active_job_info(
RESET_STATISTICS => 'NO',
SUBSYSTEM_LIST_FILTER => '' ,
JOB_NAME_FILTER => '*ALL',
CURRENT_USER_LIST_FILTER => '',
DETAILED_INFO => 'ALL'
)) A
group by subsystem, subsystem_library_name, job_type, memory_pool, system_pool_id, pool_name
order by subsystem, subsystem_library_name, job_type, memory_pool, system_pool_id, pool_name
;
Creates this output:
https://imgur.com/K5HlDrO

DSPSYSSTS
System Pool Reserved Max -------DB------- -----Non-DB-----
Pool Size (M) Size (M) Active Faults Pages Faults Pages
1 7236.9 3777.7 +++++ .0 .0 .0 .0
2 31944.9 23.5 7987 1.2 319.2 16.4 39.1
3 27705.7 .6 558 22.9 4105.1 15.9 45.6
4 1331.0 1.2 87 .0 .1 .2 5.6
5 64885.3 2.7 2863 33.2 2155.7 39.5 96.4

Rob Berendt
--
IBM Certified System Administrator - IBM i 6.1
Group Dekko
Dept 1600
Mail to: 2505 Dekko Drive
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