[infinispan-dev] First version of JBoss Marshalling based Marshaller

[Manik Surtani]

On 14 Apr 2009, at 18:10, David M. Lloyd wrote:

> On 04/14/2009 12:02 PM, Galder Zamarreno wrote:
>>> I know this is jumping the gun a little, but how does this play  
>>> with ISPN-42: Object stream pooling?  That's an optimisation I  
>>> would really like to see in place as soon as possible.  :-)  Is  
>>> this a trivial "extra" on top of ISPN-44?
>> Since streams are now retrieved from a factory in JBoss  
>> Marshalling, I need to see what it happens behind the scenes (David  
>> could give us a hint here). He might be already doing pooling of  
>> the streams returned by the factory. If he isn't, since he's  
>> already implemented the factory, it might make more sense to  
>> implement it in JBMAR than in JBC? Otherwise, we can always  
>> implement this ourselves. David, thoughts?
>
> Nope, the marshallers aren't pooled by default because they're very  
> lightweight to create (compared to Object*Streams).  You can however  
> implement pooling if you want to (the start/finish methods exist for  
> this purpose).  The potential benefit to pooling Marshaller/ 
> Unmarshaller instances is that if you have Serializable objects  
> which have readObject/writeObject methods, the special Object*Stream  
> that is used to support this API is cached on the instance.  I  
> haven't seen conclusive evidence that pooling would improve  
> performance overall though; because my Object*Streams completely  
> override the API, it doesn't have the same costs that are normally  
> associated with creating these objects (however there is still a  
> permission check involved).

Interesting.  Maybe stream pooling will not be necessary at all then  
if your streams are that much lighter/quicker to create.

--
Manik Surtani
manik at jboss.org
Lead, Infinispan
Lead, JBoss Cache
http://www.infinispan.org
http://www.jbosscache.org