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From: Latchesar Ionkov <lionkov@lanl.gov>
Subject: Re: [9fans] From our "not quite grasping the concept" file
Date: Thu,  8 Nov 2007 09:07:31 -0700
To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
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On Nov 8, 2007, at 8:20 AM, erik quanstrom wrote:

>> The opportunity still exists -- only one driver needs to implement
>> their numeric hack - 9p.  Then the rest can be based off of that.
>> Unfortunately, evolution just comes slow and painful.
>>
>>        -eric
>
> are 9p mesages really the right vehicle for this?  9p messages
> provides a serialized and in a standard byte order.  this requires
> byte reordering (on intel) and copying.  but are these really needed?
> the guest and host are on the same platform, so the guest can
> pass pointers to the host.  for the same reason, integers don't need
> reformatting.
>
> modern devices usually dma directly, so the host may never need
> to touch the pointed-to memory.
>
> perhaps using Fcall structures directly would be more efficient?

That's one of the options. We are probably going to start with  
serialized content (no copying of the data though) and if it is too  
slow, we won't do serialization.

Thanks,
	Lucho