docs: add release-note fragment for PR #2123 (#2159)

llm-d-router-release-notes[bot] · web-flow · commit 92060d803fff · 2026-07-23T20:06:13.000+03:00
Signed-off-by: llm-d-router-release-notes[bot] &lt;287676111+llm-d-router-release-notes[bot]@users.noreply.github.com&gt;
Co-authored-by: llm-d-router-release-notes[bot] &lt;287676111+llm-d-router-release-notes[bot]@users.noreply.github.com&gt;
diff --git a/release-notes.d/unreleased/2123.md b/release-notes.d/unreleased/2123.md
@@ -0,0 +1,7 @@
+---
+pr: 2123
+url: https://github.com/llm-d/llm-d-router/pull/2123
+author: LukeAVanDrie
+date: 2026-07-23
+---
+Flow control queueing is now bounded by default: `defaultRequestTTL` defaults to 60s and per-band `maxRequests` defaults to 5000 when unset. For existing flow control users this is a behavior change: an explicit `defaultRequestTTL: "0s"` disables the TTL (requests then wait until client disconnect), and a band `maxRequests`/`maxBytes` of 0 is treated as unset and receives the default. To approximate the legacy fast-fail behavior for sheddable traffic, configure a small `defaultNegativePriorityBand.maxRequests`. Scale-to-zero deployments should raise `defaultRequestTTL` above the expected cold-start time.
