Docker container eat memory and has large block I/O

I try to use Docker and I have little problem. I don't understand why there is an increase in memory usage in my container. For example:

I have container with RabbitMQ, but it's not used. When I start the container, it has only 80Mb of memory, but after ten hours, it takes all limit (256Mb). I check statistics with docker stats -a.

Also, container has huge Block I/O

UPDATE:

RabbitMQ version 3.7.8

I used standart RabbitMQ-docker-image from docker-hub, but my server has't internet connection, and I had to use export/import.

docker export rabbitmq > /work/tmp/rabbitmq-docker-imagedocker import /work/tmp/rabbitmq-docker-image rabbitmq:currentdocker run -d --memory=256m --restart=on-failure --hostname rabbitmq --name prod-rabbit -p 5673:5672 -p 15673:15672 rabbitmq:current rabbitmq-server

Result of docker stats -a

CONTAINER ID a0e8ad573154

NAME prod-rabbit

CPU % 0.12%

MEM USAGE / LIMIT 255.6MiB / 256MiB

MEM % 99.13%

NET I/O 201kB / 361kB

BLOCK I/O 19.5GB / 31.1GB

PIDS 5533

Know someone who can answer? Share a link to this question via email, Twitter, or Facebook.