Fault Tolerance 6.9.0

Today, we announce the release of SmallRye Fault Tolerance 6.9.0. This release contains an important bugfix. Upgrade is strongly recommended.

Starting with the 6.3.0 release, SmallRye Fault Tolerance emits metrics even when using the programmatic API. If there is no description set on the Guard / TypedGuard / FaultTolerance object, a UUID was used as the value of the method tag. However, at least in some metrics implementations, the keys and values of all tags are retained in memory. If a Guard / TypedGuard / FaultTolerance object is created for each action (which is relatively easy to achieve without even knowing), a fresh UUID is generated for each object. Since those UUIDs are stored in memory indefinitely, this basically amounts to a memory leak.

In this release, this memory leak is fixed. If there is no description set on the Guard / TypedGuard / FaultTolerance object, metrics are simply not emitted. This is technically speaking a breaking change, but we feel it is very much warranted. Noone likes memory leaks and OOMs happening in production.

The bug is also fixed in the 6.4.2 release, which doesn’t have an announcement. More backports might be coming.

As usual, if you have any ideas for improvements, please file an issue!