Remediation Task Rules, Calculators, and Assignment Rules use conditions during import,
created using the Condition builder. Changes to their criteria can affect
performance since each record is evaluated using these filters.
The rules and calculators shipped with the base system are optimized for performance. Editing
or creating rules or calculators takes care and may require both ServiceNow
and Vulnerability Response expertise.
Avoid filtering based on subclass fields
Some tables support extension. An example of that is the CMDB CI [cmdb_ci] table. Tables like cmdb_ci_hardware and cmdb_ci_computer extend this table. If you filter based on a field that is not on the parent table, that filter
can be expensive to construct and evaluate.
For example, filtering on Configuration Item > Cost would not adversely affect performance because Cost is a
class field, and not a subclass field, of Configuration Item.
Configuration Item > Computer, however, is a subclass requiring a dot-walk to another field, in this case, Operating System. This process can take many milliseconds which adds up quickly, when millions of vulnerable
items are being imported, and affect performance.
Note:
Using the [contains] condition is like a wild card search and can cause performance impact. Using [is], wherever possible, is more efficient.
