[wildfly-dev] WFCORE-665

[Brian Stansberry]

Hi Jay,

Re: https://issues.jboss.org/browse/WFCORE-665

I wanted to discuss this here, just because it's a potential change in 
longstanding behavior, so it could use more visibility than JIRA 
comments or pull requests get.

I think the simple solution is just to invert the priority between 
groupVM and hostVM in the call to the JVMElement constructor at

https://github.com/wildfly/wildfly-core/blob/master/host-controller/src/main/java/org/jboss/as/host/controller/ManagedServerBootCmdFactory.java#L132

There's one other analogous situation, with system properties, and there 
the host model value takes precedence over server-group. See 
ManagedServerOperationsFactory.getAllSystemProperties.

I want those two to be consistent, as I want all such precedence things 
to be consistent. (The "path" and "interface" resources are the other 
precedence things, but there "server-group" is not a factor.)

The argument for host overriding server-group is better to me than the 
opposite, so if we're picking one to be consistent with, I pick the 
former. One of the basic ideas of domain.xml versus host.xml is 
domain.xml sets the base config and then specific items can be overriden 
at the host level. So having server-group take precedence is unintuitive.

I don't like the approach in your patch because it makes the rules more 
complex. Whether host takes precedence over server-group depends on 
whether there's a jvm config at the server level with a name that 
matches one of the host level configs. That's too complicated.

Cheers,

-- 
Brian Stansberry
Senior Principal Software Engineer
JBoss by Red Hat