Large objects in headers and endpoints?

[Keith Freeman]

Hello all,

I'm considering a design where (in Java DSL) a component in my route 
would create a large object (a hashmap with thousands of entries 
totaling a few MB in size) and stick it in a header.  Then other 
components along the route would be able to access it for lookups and 
modifications.

My question is whether I need to worry about performance with this 
design, assuming I keep the entire route within a single JVM?

I do use direct:, direct-vm:, seda: and vm: endpoints in my routes, but 
my understanding is that all of these (including the header) will simply 
pass this along as an object reference, never making an copies or 
serializing it.