tomcat-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From David Jencks <>
Subject Re: Osgifing Tomcat
Date Fri, 25 Apr 2008 07:49:19 GMT

On Apr 24, 2008, at 11:11 PM, Henri Gomez wrote:

>> I've heard various claims of this nature from osgi zealots, but when
>> talking to apparent experts the only things resembling this they  
>> seemed to
>> know about were grad student experiments that did not have  
>> production use as
>> even a far-in-the-future goal.  Do you know of any actual examples  
>> of this
>> kind of behavior that actually work under load?
> We'll see how OSGI works underload with Glassfish v3.

Are they planning to support "gapless" redeployment of web apps using  
only osgi features, with no other servlet container support?  If so is  
can you point to an explanation of how they plan to do this?
> BTW, performance is only a point in an IT infrastructure, ease of
> deployment and administration is often more important (from my day to
> day experience)

I think its entirely possible for a servlet container to support  
gapless redeployment of web apps.  I don't see how this can be  
supplied or even helped by osgi itself.  As far as I can see, osgi has  
a fairly nice classloader that unfortunately requires all jars to be  
osgi-ified (a process that will take years and, judging by the  
semantically similar info in maven poms, mostly result in wrong  
information) and a fairly limited service and service dependency  
model, plus a lot of hype.  For instance I've seen this claim several  
times that osgi will by some magic make hot updates of production  
systems just work, but no one seems to be  able to tell me how its  
supposed to work.  The only actual info I've heard was about a student  
experiment that clearly would not work in a high-load environment.   
Personally I don't think this kind of feature will work as a component  
container feature without transactional memory; the only place I know  
of this being available is in haskell.

just my highly biased $0.02

david jencks

> ---------------------------------------------------------------------
> To unsubscribe, e-mail:
> For additional commands, e-mail:

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message