[U-Boot] http client?

[Robin Getz]

On Wed 22 Jul 2009 16:53, Ben Warren pondered:
> Robin Getz wrote:
> > I see:
> >
> > #define TFTP_MTU_BLOCKSIZE 1468blksize
> > static unsigned short TftpBlkSizeOption=TFTP_MTU_BLOCKSIZE;
> >
> >                 /* try for more effic. blk size */
> >                 pkt += sprintf((char *)pkt,"blksize%c%d%c",
> >                                 0,TftpBlkSizeOption,0);
> >
> > but that is it...
> >
> > No CONFIG_ options for anything else?
> >
> >   
> Right, it's hard-coded to 1468 (maximum TFTP frame that will fit in a 
> 1500-byte Ethernet frame, due to UDP overhead).  By default, TFTP 
> requests a blocksize that will fill the frame.  If not, it uses the 
> default TFTP block size (512, I think).
> 
> Is this not good enough?

When I looked at the RFC data

blocksize   no gateway   with gateway
---------   ----------   ------------
  512            23.85      37.05
 1024            16.15      25.65
 1432            13.70      23.10
 2048            10.90      16.90
 4096             6.85       9.65
 8192             4.90       6.15

it appears that the overhead of IP fragmentation and reassembly (which does 
add overhead as the number of gateways increases) may be worth the time...

-Robin