In Salesforce CPQ, Are the Values of Summary Variables Cached, or Are They Retrieved in Real Time on Calculate?

Question

In Salesforce CPQ, most standard Price Rules are pre-cached in the background during Quote Line Editor (QLE) load to minimize the performance impact.

But certain features (like Lookup Queries) are not cached, and require a server round-trip on calculate.

Are the values of Summary Variables cached, or do they also require a round-trip, resulting in a real-time aggregate value?

https://help.salesforce.com/s/articleView?id=sf.cpq_summary_variables.htm&type=5