os_mon memsup timeout problem

[ops2187]

Describe the bug

My system is using RabbitMQ 4.0.7 on Erlang 27.3
After running it for several days, this problem occurs. I use RabbitMQ purely as an IPC mechanism to allow programs to communicate with each other. (Throughput is not high.)

I would like to ask, in version 4.0.7, even if I disable the os_mon feature, will this still be triggered?
I did not make any settings in the advanced.config, but when running rabbitmqctl environment, I see the following content:"

This is my hardware information:
Windows 10 Enterprise LTSC

Thank you! ~
Albert

=======================================================================
2025-08-07 03:25:12.416000+08:00 [error] <0.158846.0> Error in process <0.158846.0> on node rabbit@@ALGSN244700363 with exit value:
2025-08-07 03:25:12.416000+08:00 [error] <0.158846.0> {{badmatch,{error,{fread,integer}}},
2025-08-07 03:25:12.416000+08:00 [error] <0.158846.0> [{memsup,get_
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> ancestors: [os_mon_sup,<0.124.0>]memory_usage,1,[{file,"memsup.erl"},{line,841}]},
2025-08-07 03:25:12.416000+08:00 [error] <0.158846.0> {memsup,'-handle_info/2-fun-0-',2,[{file,"memsup.erl"},{line,583}]}]}
2025-08-07 03:25:12.416000+08:00 [error] <0.158846.0>
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> ** Generic server memsup terminating
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> ** Last message in was {'EXIT',<0.158846.0>,
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> {{badmatch,{error,{fread,integer}}},
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> [{memsup,get_memory_usage,1,
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> [{file,"memsup.erl"},{line,841}]},
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> {memsup,'-handle_info/2-fun-0-',2,
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> [{file,"memsup.erl"},{line,583}]}]}}
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> ** When Server state == [{"Timeout",60000},
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> {"Memory Usage",
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> [{"Allocated",7583477760},{"Total",16786386944}]},
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> {"Worst Memory User",
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> [{"Pid",<0.50.0>},{"Memory",2775912}]}]
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> ** Reason for termination ==
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> ** {{badmatch,{error,{fread,integer}}},
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> [{memsup,get_memory_usage,1,[{file,"memsup.erl"},{line,841}]},
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0> {memsup,'-handle_info/2-fun-0-',2,[{file,"memsup.erl"},{line,583}]}]}
2025-08-07 03:25:12.489000+08:00 [error] <0.128.0>
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> crasher:
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> initial call: memsup:init/1
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> pid: <0.128.0>
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> registered_name: memsup
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> exception exit: {{badmatch,{error,{fread,integer}}},
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> [{memsup,get_memory_usage,1,
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> [{file,"memsup.erl"},{line,841}]},
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> {memsup,'-handle_info/2-fun-0-',2,
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> [{file,"memsup.erl"},{line,583}]}]}
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> in function gen_server:handle_common_reply/8 (gen_server.erl, line 2476)
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> message_queue_len: 0
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> messages: []
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> links: [<0.125.0>]
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> dictionary: []
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> trap_exit: true
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> status: running
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> heap_size: 6772
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> stack_size: 29
2025-08-07 03:25:12.491000+08:00 [error] <0.128.0> reductions: 1491141752

Rabbit_error_log.txt

Reproduction steps

Running it for several days, this problem occurs.

Expected behavior

The throughput is low, so it should not be the cause of this problem. Could it be related to the Windows operating system instead?

Additional context

No response

[michaelklishin]

RabbitMQ 4.0.x is out of community support.

The exception is harmless and should not affect RabbitMQ availability in any way.

memsup is a part of Erlang/OTP, not RabbitMQ. However, due to how RabbitMQ starts that dependency, the settings from advanced.config won't be loaded early enough for memsup to pick them up.

#13759 (comment) explains what needs to change for the settings you are listing to get to memsup early enough to have an effect.

The change isn't significant in scope, so anyone who cares enough can contribute it.

[ops2187]

Thanks!

[lukebakken]

rabbitmq-users discussion

[ops2187]

Thanks!