Description of problem:
It has been identified that the following candlepin jobs will run with very long times and potentially fail with memory issues on tomcat:

ExpiredPoolsCleanupJob
RegenEnvEntitlementCertsJob

Version-Release number of selected component (if applicable):
Satellite 6.9.6-1
candlepin-3.1.28-1

How reproducible:
Every time

Steps to Reproduce:
1. Have a Satellite with 54,000 hosts with 1 subscription expire at the same time.
2. Watch tomcat usage reach 24GB+ memory usage
3.

Actual results:
Multiple attempts to complete the job as it has a restart if memory issues are encountered.
Long run times for these jobs with thousands of hosts

Expected results:
The job should be run in smaller batches assumed from a value in the configuration file.
IE:
while ExpiredPoolsExist:
PoolBatchSize = config.parser(candlepin.poolbatchsize)
if PoolBatchSize = '':
set PoolBatchSize = 2000
ExpiredPoolsCleanupJob(ExpiredPoolsList[:PoolBatchSize])

Additional info:
Configuring this for large deployments would also be needed to be added for the performance tuning guide as more memory is allocated to tomcat to process larger batches.