BizTalk memory behavior

Recently, as my application grew; the memory consumption of the bts service host had increased notably. We've looked to mitigate these effects by switching to "presumably less-consuming adapters" such as wcf. We've changed the variable/messages within the scopes hoping that this will decrease the memory consumption as well. Nothing seems to have worked.

In first instance, almost any orchestration get the memory on the loose, (400Mbs and so); so, as a consequence the system began to throttle due to the lack of system memory condition. If we cut the throttling lock, by setting to 0, the service will inevitable crash due to "sytem.outofmemoryex".

We use the sql adapter as well, we use maps that are not so complex, some are xslt inlined, some are direct linking, some are using external xslts.Our scopes a few of them are transactional, other are set to non-transactional, they are just catching exceptions.

So, the question is, what shapes are highly memory consumption, what recommendations are usually referred to avoid these high memory ?

* Using BTS2006R2.