Performance impact of "individual" catalog entry promotions
Promotion types that offer discounts on individual catalog entries can degrade site performance because of the amount of processing required while a customer checks out.
If you use one of these promotion types, and a customer purchases many catalog entries (hundreds or more) that qualify for the promotion, the promotion engine processes adjustments on each item individually at checkout. As a result, site performance can be degraded during this processing. Site traffic and system capacity are other factors that affect site performance in this situation. When you are creating a promotion that is based on an individual catalog entry, consider specifying redemption limits to limit the quantity for catalog entries. By limiting the quantity for catalog entries, you can limit the performance impact when you use promotion types that are based on individual catalog entries.
To avoid the potential performance impact of individual catalog entry promotion types, consider creating promotions that offer discounts on the subtotal of all qualifying catalog entries. The following promotion types offer discounts on the subtotal of all qualifying catalog entries:
- Amount off the subtotal of catalog entries
- Amount off the subtotal of catalog entries from a category
- Percentage off the subtotal of catalog entries
- Percentage off the subtotal of catalog entries from a category
- Fixed price on the subtotal of catalog entries
- Fixed price on the subtotal of catalog entries from a category
Using these alternative promotion types means that any Redemption Limits or Maximum Discount Amount properties you set apply at the order level rather than to each individual catalog entry. However, this trade-off can be worthwhile to ensure that site performance is not impacted. For more information, see Comparison of "individual" and "subtotal" percentage off promotion types.
The administrator can configure order boundaries to prevent unbound exceptions. For information, see Configuring Order boundaries to prevent unbound exceptions. You can limit the maximum quantity in a shopping cart; then, the site can use "individual" type promotions.