fix(quic-interop): detect multiplexing by URL count, not TESTCASE name

The smoking gun from the 2026-05-07 multiplex run boot log: [boot] DEBUG=1; ...; TESTCASE=transfer; ROLE=client [boot] transfer mode: parallel=false urls=1999 quic-interop-runner sets TESTCASE_CLIENT=transfer for ALL the transfer-family testcases (transfer, multiplexing, transferloss, transfercorruption). Discrimination between transfer (1 file) and multiplexing (~2000 files) happens by URL count, NOT by TESTCASE name — so our check `parallel = (testcase == "multiplexing")` was always false, even for the multiplexing test, and we always took the serial fallback path: client.get(authority, path) per URL, opening one stream + awaiting before the next. That's why the wire showed exactly one stream per RTT for the entire 60s. Fix: parallel = (token count of REQUESTS env var) > 1. Effectively: - 1 URL → transfer testcase, serial path - >1 URL → multiplexing testcase, batched-parallel path Verified the writer's batched coalescing already works in unit tests (MultiplexingCoalescingTest, MultiplexingAioquicTpsTest both green at ~9 streams/packet). With this dispatch fix, the live runner should finally reach the batched code path. Bumped WRITER_DEBUG_BUILD_ID so the next [boot] line confirms the fix is deployed.
2026-05-07 14:24:52 +00:00
parent a9dc927cc6
commit ac0d6f06a9
2 changed files with 16 additions and 2 deletions
@@ -198,7 +198,21 @@ fun main() {
                    initialVersion = initialVersion,
                    keyLogPath = keyLogPath,
                    qlogDir = qlogDir,
-                    parallel = (testcase == "multiplexing"),
+                    // The runner reuses TESTCASE_CLIENT=transfer for the
+                    // multiplexing testcase — discrimination is by URL
+                    // count, not testcase name. We were checking
+                    // testcase == "multiplexing" which is NEVER true
+                    // (we'd see TESTCASE=multiplexing only on a
+                    // hypothetical client where the runner explicitly
+                    // sets it). Symptom: 60s timeout with 1421/2000
+                    // files at 1 stream / RTT — exactly the serial
+                    // client.get(...) path. Confirmed via the boot log:
+                    //   [boot] TESTCASE=transfer; transfer mode:
+                    //   parallel=false urls=1999
+                    //
+                    // Cheap whitespace tokenization here just counts;
+                    // runTransferTest re-parses into URI[] inside.
+                    parallel = requests.split(Regex("\\s+")).count { it.isNotBlank() } > 1,
                )
            }