More 4.0 release notes updates post-#11937

release-notes/4.0.0.md

@@ -47,13 +47,18 @@ on how to migrate to quorum queues for the parts of the system that really need
 Quorum queues now have a default [redelivery limit](https://www.rabbitmq.com/docs/next/quorum-queues#poison-message-handling) set to `20`.
 Messages that are redelivered 20 times or more will be [dead-lettered](https://www.rabbitmq.com/docs/dlx) or dropped (removed).
 
-This limit is necessary to protect nodes from consumers that run into infinite crash-requeue-crash-requeue loops. Such
+This limit is necessary to protect nodes from consumers that run into infinite fail-requeue-fail-requeue loops. Such
 consumers can drive a node out of disk space by making a quorum queue Raft log grow forever without allowing compaction
 of older entries.
 
 If 20 deliveries per message is a common scenario for a queue, a dead-lettering target must be configured
 for such queues. The recommended way of doing that is via a [policy](https://www.rabbitmq.com/docs/parameters#policies).
 
+The limit can be [increased](https://www.rabbitmq.com/docs/next/quorum-queues#poison-message-handling) using a policy.
+This option is recommended against: usually the presence of messages that have been redelivered 20 times or more suggests
+that a consumer has entered a fail-requeue-fail-requeue loop, in which case even a much higher limit
+won't help avoid the dead-lettering.
+
 ### CQv1 Storage Implementation was Removed
 
 CQv1, [the original classic queue storage layer, was removed](https://github.com/rabbitmq/rabbitmq-server/pull/10656)
@@ -167,13 +172,18 @@ periods of time (no more than a few hours).
 
 ### Recommended Post-upgrade Procedures
 
-#### Configure Dead Lettering for Frequently Redelivered Messages
+#### Configure Dead Lettering or Increase the Limit for Frequently Redelivered Messages
 
 In environments where messages can experience 20 redeliveries, the affected queues should have [dead lettering](https://www.rabbitmq.com/docs/dlx)
 configured (usually via a [policy](https://www.rabbitmq.com/docs/parameters#policies)) to make sure
 that messages that are redelivered 20 times are moved to a separate queue (or stream) instead of
 being dropped (removed) by the [crash-requeue-redelivery loop protection mechanism](https://www.rabbitmq.com/docs/next/quorum-queues#poison-message-handling).
 
+Alternatively, the limit can be [increased](https://www.rabbitmq.com/docs/next/quorum-queues#poison-message-handling) using a policy.
+This option is recommended against: usually the presence of messages that have been redelivered 20 times or more suggests
+that a consumer has entered a fail-requeue-fail-requeue loop, in which case even a much higher limit
+won't help avoid the dead-lettering.
+
 
 ## Changes Worth Mentioning