== 6. mechanism proof ==
before: rows=4 visits=3 qlen=0
20 hits codes: 204 204 204 204 204 204 204 204 204 204 204 204 204 204 204 204 204 204 204 204
after 20 hits: rows=4 (delta 0, EXPECT 0: acked but queued) qlen=20 (EXPECT 20)
6 more hits codes: 204 204 204 204 204 204
after 26 hits (+1s): rows=29 (delta 25, EXPECT 25: one in-request batch) qlen=1 (EXPECT 1: the tail below the 25 threshold)
-- drain the tail with the vendor's own command --
Force proccess num requests at once: 1
Starting to process request sets, this can take a while

This worker finished queue processing with 3.66req/s (1 requests in 0.27 seconds)

after drain: rows=30 (delta 26, EXPECT 26) visits=29 (delta 26, EXPECT 26 distinct visitors) qlen=0 (EXPECT 0)
MECHANISM 204-then-queue proven: 20 acked hits stored 0 rows until the 25th; tail drained by queuedtracking:process
QUEUED_OK
