about the snd-base/hot-spot of flexpage mapping

[Adam Lackorzynski]

Hi,

On Thu Oct 31, 2013 at 19:24:32 +0800, ·ëϣ˳ wrote:
> I have a question about the snd-base/hot-spot of flexpage mapping feature.
> in many l4 documents, there are a lot of words about the snd-base/hot-spot
> concept, it seem that are a complex mechanism to calculate the send base
> when the sender's flexpage have different size compares to receiver's
> flexpage, I have read a lot of documents(l4 user manual/l4 reference manual
> etc.) about this mechanism, but I can not figure out it... Could you tell
> why l4 needs this mechanism, and what situation that this mechanism adapt
> to?

You might want to look at the corresponding lecture slides:
http://www.inf.tu-dresden.de/index.php?node_id=1314&ln=en (Memory).
Basically with the send-base the sender can specify where to place the
mapping in the receiver, for example, when resolving a page-fault the
receive window of the faulting thread is the whole address space, so the
sender must specify where to put the sent page.

> And I have another question to Dresden University guys: what is the l4
> version of Fiasco.OC based?

Fiasco.OC defines its own interfaces, i.e. it evolved from previous L4
versions. It probably means it defines its own version.




Adam
-- 
Adam                 adam at os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/