Alignment in the binary protocol

Brian Aker brian at
Tue Mar 18 13:54:24 UTC 2008


So I have not looked at the code yet concerning this bit.... Is the  
code safe from byte alignment problems between different endian hosts/ 


On Mar 18, 2008, at 4:59 AM, Trond Norbye wrote:

> Hi,
> I have been testing the binary protocol the last few days and I  
> would like to suggest that we swap the order some fields to solve  
> some alignment problems.
> The cas-id is a 64-bit datatype and will require 8-byte alignment on  
> some hardware, but it is placed on a 4-byte alignment in the get  
> response. The current get-response contains a 16 byte header  
> followed by the 4 byte flags-field causing the wrong alignment for  
> the cas id. If we swap the order on the two fields the cas-id will  
> get proper alignment, and we can access the field directly as an  
> uint64_t...
> To be consistent I suggest that we move the cas-id to the front in  
> the set/add/replace command as well. The attached patch implements  
> this.
> Trond
> <alignment.patch.gz>

Brian "Krow" Aker, brian at
Seattle, Washington                     <-- Me                <-- Software
You can't grep a dead tree.

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