mqtt_node High memory usage。 version：3.8.14

[feiniao886]

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Thank you.

[michaelklishin]

I will convert this issue to a GitHub discussion. Currently GitHub will automatically close and lock the issue even though your question will be transferred and responded to elsewhere. This is to let you know that we do not intend to ignore this but this is how the current GitHub conversion mechanism makes it seem for the users :(

[michaelklishin]

There isn't much we can recommend beyond the tools that provide a breakdown of memory used by a node.

[michaelklishin]

This sounds like a duplicate of #2863 now. Upgrade to 3.8.14 which includes #2692 (well, 3.8.10 does but there is no reason to not use the latest patch release).

[feiniao886]

The current link has been removed
The current number of connections is 0
mqtt-node Memory usage has been growing.

all queue type is classic.

[kjnilsson]

hm it is still executing the old, inefficient code which means the mqtt machine has not upgraded itself to the current version yet. Is this a clustered environment or a single node RabbitMQ?

[feiniao886]

clustered environment

Did the update succeed?

Such an operation:
systemctl stop rabbitmq-server
yum install rabbitmq-3.8.14xxx.rpm
systemctl start rabbitmq-server

What should I do, reinstall?

[kjnilsson]

Are all nodes up to date?

Anyhow you could try decommissioning then disabling the plugin on all nodes as described here https://www.rabbitmq.com/mqtt.html#disabling-plugin

then restart + re-enabling the plugin.

If that fails (it may time out) you could try the nuclear approach of disabling the MQTT plugin, moving all files and folders inside the mnesia/quorum directory on each node to a temporary location, followed by a restart of all nodes then re-enablement of the plugin.

[feiniao886]

thank you so much for your suggestion.
After resetting, the problem was resolved.
The current operating status is stable
thx, thx !!!