I wouldn't think so. But then again, why do you need this? The deployment manager gives you this functionality (rule updates), although the entire service is reset on rule changes.
Expensive in terms of what?
Your system will obviously need to compile the rule project, but this is handled by a separate thread (the deployment manager). When the compilation is complete, the deployment manager tells the server that it has a new version of the rules, and the server switches.
You can configure how this affects service requests, but the defaults are that ongoing requests are completed using the old version of the rules, whereas new requests are handled by the new version.
Working memory is a per-request thing, and is not affected/will not affect the service reset.
That is obviously the best solution :-)
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