diff --git a/bench/MemBench.hs b/bench/MemBench.hs
index 7be41611c..69e2ca2ce 100644
--- a/bench/MemBench.hs
+++ b/bench/MemBench.hs
@@ -23,7 +23,7 @@
 --
 -- Single-server phases (server on testPort):
 --   plain | svc | svcrace | ntf | conc | svcsubs | getp | stuck | certchurn | link | ntfexp
---   ntfloop | ntfdeliver | subslice | conns | load | cpsave  -- PostgreSQL build only
+--   ntfloop | ntfdeliver | subslice | conns | load | prodmix | cpsave  -- PostgreSQL build only
 --   tlsstall | tlshalf | tlschurn | tlspartial  -- TLS/TCP stack
 --
 -- Two-server phases (proxy on testPort, lagged destination relay on testPort2):
@@ -48,6 +48,7 @@ import Data.ByteString.Char8 (ByteString)
 import Data.Int (Int64)
 import Data.Foldable (toList)
 import Data.List.NonEmpty (NonEmpty (..), fromList)
+import qualified Data.Map.Strict as M
 import Data.Maybe (fromMaybe)
 import Data.Time.Clock (diffUTCTime, getCurrentTime)
 import qualified Data.X509.Validation as XV
@@ -685,6 +686,140 @@ runLoadClient g = do
   n <- readTVarIO ops
   putStrLn $ "DONE " <> show n <> " " <> show (realToFrac (diffUTCTime end start) :: Double)
 
+-- Production-shaped server memory: C connections (PROD_CONNS, default 1000) each subscribing
+-- Q queues (PROD_QUEUES, default 20) in batches of up to 100 per block, as the agent resubscribes,
+-- plus PROD_NEW subscriptions per connection created with NEW; then PROD_SEC seconds (default 60)
+-- of traffic where PROD_SENDERS connections (default 16) send to random queues and every recipient
+-- acknowledges its messages. The client runs in a child process (phase prodclient); this process
+-- reports the server's live heap, memory in use and RSS when idle and at peak under traffic.
+runProdMix :: IO ()
+runProdMix = do
+  base <- liveBytesMiB
+  rssBase <- rssMiB
+  exe <- getExecutablePath
+  (Just hIn, Just hOut, _, ph) <- createProcess (proc exe ["prodclient", "0"]) {std_in = CreatePipe, std_out = CreatePipe}
+  hSetBuffering hIn LineBuffering
+  (conns, subs) <- awaitLine hOut "READY" >>= \case
+    [c, n] -> pure (read c, read n) :: IO (Int, Int)
+    _ -> fail "bad READY line"
+  idle <- liveBytesMiB
+  idleStats <- getRTSStats
+  idleRss <- rssMiB
+  printf "prodmix: IDLE connections=%d subscriptions=%d live=%.1f MiB (%.2f KiB/conn) mem_in_use=%.1f MiB rss=%.1f MiB (base live=%.1f rss=%.1f)\n"
+    conns subs (idle - base) ((idle - base) * 1024 / fromIntegral conns) (mib $ gcdetails_mem_in_use_bytes $ gc idleStats) idleRss base rssBase
+  hPutStrLn hIn "GO"
+  peak <- newTVarIO (0 :: Double, 0 :: Double, 0 :: Double)
+  done <- newEmptyTMVarIO
+  let sampler = do
+        threadDelay 2000000
+        st <- getRTSStats
+        r <- rssMiB
+        atomically $ modifyTVar' peak $ \(m, l, rs) -> (max m (mib $ gcdetails_mem_in_use_bytes $ gc st), max l (mib $ gcdetails_live_bytes $ gc st), max rs r)
+        atomically (isEmptyTMVar done) >>= (`when` sampler)
+  msgs <- withAsync sampler $ \_ -> do
+    [n] <- awaitLine hOut "DONE"
+    atomically $ putTMVar done ()
+    pure (read n :: Int)
+  (pkMem, pkLive, pkRss) <- readTVarIO peak
+  end <- getRTSStats
+  after <- liveBytesMiB
+  printf "prodmix: TRAFFIC messages=%d peak_mem_in_use=%.1f MiB peak_live_after_gc=%.1f MiB peak_rss=%.1f MiB live_after=%.1f MiB major_gcs=%d gc_cpu=%.1fs mutator_cpu=%.1fs\n"
+    msgs pkMem pkLive pkRss (after - base) (major_gcs end - major_gcs idleStats)
+    (fromIntegral (gc_cpu_ns end - gc_cpu_ns idleStats) / 1e9 :: Double) (fromIntegral (mutator_cpu_ns end - mutator_cpu_ns idleStats) / 1e9 :: Double)
+  hClose hIn
+  void $ waitForProcess ph
+  where
+    mib :: Word64 -> Double
+    mib b = fromIntegral b / (1024 * 1024)
+    awaitLine :: Handle -> String -> IO [String]
+    awaitLine h tag = hGetLine h >>= \l -> case words l of
+      (t : rest) | t == tag -> pure rest
+      _ -> awaitLine h tag
+
+-- resident set size of this process, from /proc
+rssMiB :: IO Double
+rssMiB = do
+  ls <- lines <$> readFile "/proc/self/status"
+  pure $ case [w | l <- ls, ("VmRSS:" : w : _) <- [words l]] of
+    (kb : _) -> read kb / 1024
+    _ -> 0
+
+runProdClient :: TVar ChaChaDRG -> IO ()
+runProdClient g = do
+  hSetBuffering stdout LineBuffering
+  let env k d = fromMaybe d . (>>= readMaybe) <$> lookupEnv k
+  conns <- env "PROD_CONNS" 1000
+  nq <- env "PROD_QUEUES" 20
+  newPer <- env "PROD_NEW" 2
+  secs <- env "PROD_SEC" 60
+  senders <- env "PROD_SENDERS" 16
+  let creators = 8 :: Int
+      total = conns * nq
+  -- queues are created on a few connections first, as if by earlier sessions
+  created <- forConcurrently ([0 .. creators - 1] :: [Int]) $ \w -> benchClient $ \h ->
+    forM [i | i <- [0 .. total - 1], i `mod` creators == w] $ \i -> do
+      (rPub, rKey, dhPub) <- genKeys g
+      Resp _ _ (Ids rId sId _) <- signSendRecv h rKey (B.pack $ "c" <> show i, NoEntity, New0 rPub dhPub)
+      pure (rId, sId, rKey)
+  let qs = concat created
+      perConn = chunksOf nq qs
+  subscribed <- newTVarIO (0 :: Int)
+  go <- newEmptyTMVarIO
+  stop <- newEmptyTMVarIO
+  sIdsVar <- newTVarIO ([] :: [SenderId])
+  received <- newTVarIO (0 :: Int)
+  let recipient cqs = benchClient $ \h -> do
+        forM_ (chunksOf 100 cqs) $ \b -> do
+          let sub (rId, _, rKey) = Right $ signTransmission h rKey Nothing (B.pack "s", rId, SUB)
+          void $ tPut h (fromList $ map sub b)
+          awaitResponses h (length b)
+        newQs <- forM ([1 .. newPer] :: [Int]) $ \i -> do
+          (rPub, rKey, dhPub) <- genKeys g
+          Resp _ _ (Ids rId sId _) <- signSendRecv h rKey (B.pack $ "n" <> show i, NoEntity, New rPub dhPub)
+          pure (rId, sId, rKey)
+        let keys = M.fromList [(rId, rKey) | (rId, _, rKey) <- cqs ++ newQs]
+        atomically $ do
+          modifyTVar' sIdsVar ([sId | (_, sId, _) <- cqs ++ newQs] ++)
+          modifyTVar' subscribed (+ (length cqs + length newQs))
+        -- acknowledge every delivered message until the run is released
+        withAsync (forever $ tGetClient h >>= mapM_ (ack h keys)) $ \_ -> atomically $ readTMVar stop
+      ack h keys = \case
+        (_, rId, Right (MSG RcvMessage {msgId})) | Just rKey <- M.lookup rId keys -> do
+          let t = signTransmission h rKey Nothing (B.pack "a", rId, ACK msgId)
+          void $ tPut h [Right t]
+          atomically $ modifyTVar' received (+ 1)
+        _ -> pure ()
+      sender w = benchClient $ \h -> do
+        atomically $ readTMVar go
+        sIds <- readTVarIO sIdsVar
+        let n = length sIds
+            loop i t0 = do
+              t <- getCurrentTime
+              when (diffUTCTime t t0 < fromIntegral (secs :: Int)) $ do
+                let sId = sIds !! ((i * 7919 + w * 104729) `mod` n)
+                void $ sendRecv h (Nothing, B.pack (show i), sId, _SEND "hello")
+                loop (i + 1) t0
+        getCurrentTime >>= loop 0
+  withAsync (forConcurrently_ perConn recipient) $ \rs -> do
+    atomically $ readTVar subscribed >>= \n -> when (n < total + conns * newPer) retry
+    putStrLn $ "READY " <> show conns <> " " <> show (total + conns * newPer)
+    "GO" <- getLine
+    atomically $ putTMVar go ()
+    forConcurrently_ ([1 .. senders] :: [Int]) sender
+    n <- readTVarIO received
+    putStrLn $ "DONE " <> show n
+    void (E.try getLine :: IO (Either E.IOException String))
+    atomically $ putTMVar stop ()
+    wait rs
+  where
+    chunksOf k xs = case splitAt k xs of
+      (c, []) -> [c | not (null c)]
+      (c, rest) -> c : chunksOf k rest
+    awaitResponses :: H -> Int -> IO ()
+    awaitResponses h n = when (n > 0) $ do
+      rs :: NonEmpty (Transmission (Either ErrorType BrokerMsg)) <- tGetClient h
+      awaitResponses h (n - length rs)
+
 -- Client side of subslice: creates the subscriptions, prints "READY <subscribed>", and holds the
 -- connection until stdin is closed.
 runSubClient :: TVar ChaChaDRG -> Int -> IO ()
@@ -1411,6 +1546,8 @@ main = do
       else if phase == "connclient" then runConnClient iters
       else if phase == "load" then postgressBracket benchDBConnectInfo $ withSmpServerConfigOn (transport @TLS) benchPgCfg benchPort $ \_ -> runLoad
       else if phase == "loadclient" then runLoadClient g
+      else if phase == "prodmix" then postgressBracket benchDBConnectInfo $ withSmpServerConfigOn (transport @TLS) benchPgCfg benchPort $ \_ -> runProdMix
+      else if phase == "prodclient" then runProdClient g
 #endif
       else withSmpServerConfigOn (transport @TLS) srvCfg testPort $ \_ -> settle leakDiagSec $ do
         threadDelay 250000