Affected Versions: 3.x and 4.x
There is a slow memory leak in the Directory provider when the "Is AD" flag is selected to permit delta scans. This leak is caused by an underlying issue in System.DirectoryServices when using a DirSync control.
Memory consumed by the directory scan does not remain in committed memory and does not appear in Task Scheduler. The issue arrises if the amount of memory consumed exceeds the page file size limit resulting in an out of memory error.
There are two potential workarounds:
1. Use Task scheduler to implement a periodic restart of Panel Service, e.g. weekly or every few days
2. Instead of using the LDAP scan step in the scheduler, use Run Program steps which call Panel Tool:
Arguments: --directory <ProviderName> --full|--delta