Clojurians Log v2

at work, we use pedestal interceptors for data processing. we have a new service that consumes form kafka and sends out requests and spend like 99% of its time waiting. i was curious how hard it would be to make use of virtual threads and it ended up being super easy. putting this snippet first in chain increased throughput tremendously. using a semaphore to apply back pressure otherwise it consumes so many events from kafka simultaneously that it runs out of memory.

(def vthread
  "Lifts interceptor execution into a VirtualThread."
  (let [semaphore (Semaphore/new 1000 true)]
    {:name  ::vthread
     :enter (fn [context]
              (Semaphore/.acquire semaphore)
              (Thread/startVirtualThread
               (fn []
                 (try (chain/execute context)
                      (finally (Semaphore/.release semaphore)))))
              (chain/terminate context))}))