On 12/12/13 12:03 PM, Jesper Pedersen wrote:
On 12/12/2013 12:38 PM, Brian Stansberry wrote:
> 4) My intent is to make the default values for these attributes
be
> "false". I won't change any default though unless the relative
compoent
> lead has indicated agreement in this thread or elsewhere.
>
> But, if you disagree with "false" as the default, please let's use
this
> thread to sort that out, get input from the performance team, etc, so we
> can have at least a clear understanding of why some uses have 'true'.
>
IronJacamar uses statistics internally in order to display run-time
information of the pools.
IronJacamar 1.1.2+ has a change which will allow to turn-off statistics,
but that results in nothing is displayed to the users in that case.
If we turn-off statistics by default we will have to be careful on what
to communicate to the users, since they will expect see basic
information out of the box. Maybe IronJacamar can display more
information than the core pool settings, but requires further investigation.
I think in order to turn it off we need proof that there is a huge
benefit for standard work loads. In the end we are talking about an
extra section in the guide that explains turning off statistics will
increase performance. Nothing new there. Or ship a "performance" profile.
Just so we are on the same page, the IronJacamar statistics is done by 2
x System.currentTimeMillis() + a call to Atomic(Long|Integer|...) - let
the flame war begin :) As always, patches welcome.
> Jesper, ^^^. ;-)
>
Why do you single me out, dude ;)
You're the guy who argued for 'true'!
>
> That's for WF 8. For the next release I recommend that we also create
> subsystem-level attributes to hold the default value for the several
> cases where this setting is only configurable on a per-deployment level.
> An example would be the jpa subsystem could have a statistics-enabled
> attribute that drives the setting for all persistence units unless the
> PU descriptor overrides or the admin overrides using the existing
> per-deployment attribute. Besides being an aid to usability, having an
> attribute that ends up in the persistent configuration will also help
> deal with issues where, for example, the desired default for WildFly is
> different than the desired default for some future EAP release. The
> standard configs for the EAP release can just use a different value.
>
>
Sounds good, although having it as an option in each deployment
descriptor for each component type maybe overkill. I think an option in
wildfly.xml would be enough, and then override through
statistics-enabled via CLI.
My previous post wasn't meant to propose making this configurable in
deployment descriptors (although maybe that's a good idea; I haven't
really thought about it.) I mentioned the PU descriptor just because I
was using JPA as an example and IIRC config in the DD is part of that
particular example. Hibernate lets the user enable/disable statistics
via a property in persistence.xml.
--
Brian Stansberry
Principal Software Engineer
JBoss by Red Hat