Containers are dropped silently and randomly due to resources on deploy()

[gapan]

Here is an example scenario: on a host with 16GB RAM, I'm trying to run 20 containers with 1GB RAM allocated each.

When running fogify.deploy() I get an OK message, that everything is deployed. But that is not true. In fact, at least 4 of my containers are never started and the choice seems to be random. It appears that fogify checks the sum of resources needed against the host system and does not start any containers that exceed the host system resources (but not the actual available host resources, i.e. it checks against the total of 16GB, but not against the 8GB that may possible be actually available at that point, I guess that's another issue?).

I'm not sure if not starting the containers at all is the right course of action here. After all, I am able to start as many (or more) such containers in my system without fogify, or even by using fogify and setting lower RAM limits. But my main issue is that it all happens silently and the user is left to believe that everything went well and all containers are up.

[gapan]

I should probably mention that I'm seeing this with the v0.01 containers that are up on dockerhub.

[MosesSymeonidis]

First of all, thank you for using Fogify.

About the host's and available resources, you are right. Fogify utilizes Docker Swarm at this version, so Swarm only evaluates system resources without considering the "real"/available resources.

In this version, the system considers deployment as successful only if the docker services are deployed on Docker Swarm, and it does not take into account the state of the containers. Specifically, the controller "asks" the docker swarm if the services are deployed, and how many containers are expected to run. If the number of expected emulated nodes is the same as the count of expected containers, Fogify considers that the containers are going to be executed. I am working on this issue to provide a more accurate procedure for that, and I will try to provide a solution in the next release.