[wildfly-dev] "Boot time" system props in the managed server's model

[Jason Greene]

> On Feb 5, 2015, at 11:46 AM, Brian Stansberry <brian.stansberry at redhat.com> wrote:
> 
> On 2/5/15 11:33 AM, Jason Greene wrote:
>> 
>>> On Feb 5, 2015, at 11:24 AM, Brian Stansberry <brian.stansberry at redhat.com> wrote:
>>> 
>>> On 2/5/15 11:13 AM, Kabir Khan wrote:
>>>> 
>>>>> On 5 Feb 2015, at 16:39, Brian Stansberry <brian.stansberry at redhat.com> wrote:
>>>>> 
>>>>> tl;dr
>>>>> 
>>>>> We have a minor anomaly in system property processing in domain mode
>>>>> that we intend to ignore.
>>>>> 
>>>>> long version
>>>>> 
>>>>> While digging into a bug Emmanuel Hugonnet noticed an anomaly. When you
>>>>> define a system-property resource in domain.xml or host.xml with
>>>>> "boot-time=true", the HC does both of the following when it launches a
>>>>> server:
>>>>> 
>>>>> 1) Uses -D to set the prop when it starts the server process.
>>>>> 
>>>>> 2) Adds an add system-property op to the server's set of boot ops, which
>>>>> causes the system property to get set again later during boot.
>>>>> 
>>>>> Really, only 1) should happen; that's what "boot-time=true" means. The
>>>>> purpose of boot-time=true is to ensure the value is set at JVM launch,
>>>>> not waiting for management ops to execute, which may be too late for
>>>>> props that are read early.
>>>> I am not 100% convinced.
>>> 
>>> Me neither. :)
>>> 
>>> 1) should of course happen. But it could be argued that something in the
>>> domain management model should always be reflected in the resulting
>>> server management model. It feels a bit weird to make random exceptions.
>>> 
>>> It's similar to a jvm setting. It's a configuration of how the HC behaves.
>> 
>> If I understand correctly, the add op generated on all servers sets a system property, which activates at runtime correct?
>> 
> 
> Yes, but the property has already been set, via -D when the process was started. So it's redundant.
> 
>> 

Well I’m talking about the case where the server is already running and has not yet restarted. Perhaps that is why it does this?

--
Jason T. Greene
WildFly Lead / JBoss EAP Platform Architect
JBoss, a division of Red Hat