RabbitMQ 3.6.16-rc.1
Pre-releaseRabbitMQ 3.6.16 RC1
RabbitMQ 3.6.16 RC1 is a release candidate of a maintenance release.
Upgrades and Compatibility
See the Upgrades documentation guide for general
documentation on upgrades.
This release nearly exclusively contains backports of bug fixes, optimisations and small enhancements
(e.g. safer defaults) from the 3.7.x series. Some of them are potentially breaking but
should only affect a very small percentage of users. They are:
- The max 255 priority cap is now enforced at all levels
- Default
rabbit.channel_max
value is now about 2K, a much safer value than 65K used previously - Default idle LDAP connection timeout is now 300 seconds instead of infinity
This release has no other known incompatibilities with versions 3.6.7 through
3.6.15. See the upgrade and compatibility sections in the 3.6.7 release
notes
if upgrading from an earlier release.
3.6.x Series Support Timeline
Please read this node on RabbitMQ 3.6.x series support
timeline.
Core Server
Bug Fixes
-
Queue master locator
min-masters
incorrectly calculated the number of masters.GitHub issue: rabbitmq-server#1519
-
Maximum supported number of queue priorities (255) is now enforced.
GitHub issue: rabbitmq-server#1590
Enhancements
-
queue.delete
operations will now force delete queues that don't have a promotable
master.GitHub issue: rabbitmq-server#1501
-
ha-promote-on-failure
is a new mirrored queue setting that's similar toha-promote-on-shutdown
but for unexpected master termination.GitHub issue: rabbitmq-server#1578
-
Lock contention in internal database is now much lower when a node with a lot of exclusive queues
shuts down or is otherwise considered to be unavailable by peers. This means fewer CPU cycles
spent cleaning up the exclusive queues.
GitHub issue: rabbitmq-server#1570
-
Default max number of channels allowed on a connection (a.k.a.
channel_max
) has been lowered from65535
to2047
.
The new default is much safer and will reduce the effect application channel leaks have on node resource consumption. This is a potentially breaking change.Systems where a lot (at least hundreds) of channels per connection are used should explicitly override
channel_max
in the config file to a higher suitable value, e.g.:
[
{rabbit, [
{channel_max, 4000}
]}
].
GitHub issue: rabbitmq-server#1593
Management Plugin
Bug Fixes
-
Eliminated unnecessary encoding conversions that could lead to increased memory consumption.
GitHub issue: rabbitmq-management#550
-
rabbitmqadmin
could run into an exception with certain formatting settings on Python 2.x.GitHub issue: rabbitmq-management#568
-
rabbitmqadmin
incorrectly encoded spaces in connection name valuesGitHub issue: rabbitmq-management#579
-
HTTP API stats documentation used incorrect field names.
GitHub issue: rabbitmq-management#561
Enhancements
-
Reduced padding usage in tables in the management UI.
GitHub issue: rabbitmq-management#541
LDAP Plugin
Bug Fixes
-
LDAP server-initiated connection closure was not handled gracefully by connection pool.
Kudos to Adam Gardner for doing all the hard work investigating this issue.GitHub issues: rabbitmq-auth-backend-ldap#82, rabbitmq-auth-backend-ldap#90
-
rabbit.idle_timeout
now defaults to 300 seconds instead ofinfinity
.GitHub issue: rabbitmq-auth-backend-ldap#81
Upgrading
To upgrade a non-clustered RabbitMQ simply install the new version. All
configuration and persistent message data are retained. When upgrading
using definitions export/import from versions earlier than 3.6.0, see
http://rabbitmq.com/passwords.html.
To upgrade a RabbitMQ cluster, follow the instructions in RabbitMQ
documentation.
Source code archives
Warning: The source code archive provided by GitHub only contains
the source of the broker, not the plugins or the client libraries.
Please download the archive named rabbitmq-server-3.6.16.tar.xz
.