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<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Hello all<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>I have an idea about the implementation of zero-copy on
RTEMS’s TCP/IP stack.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>The major concept about zero-copy is decrease the copy
time of mbuf->m_data to application’s buffer,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>So I try to allocate mbuf chain in application and swap
the appended cluster buffer between protocol<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>and application in socket layer. I have implemented in
my test platform and got a lot of increase of performance/<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Was anyone did this before? I hope someone can point
out more detail that I should aware of .<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>RX sequence!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>MAC HW fill driver’s allocated mbuf->m_data(Cluster
buffer ) -> TCP/IP -> swap cluster buffer in socket layer </span></font><font
size=1 face=Wingdings><span lang=EN-US style='font-size:9.0pt;font-family:Wingdings'>à</span></font><font
size=1 face=Arial><span lang=EN-US style='font-size:9.0pt;font-family:Arial'> return
to Application.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>TX sequence!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Application fill the data in mbuf->m_data(Cluster buffer
) -> Swap cluster buffer in socket layer -> TCP/IP -</span></font><font
size=1 face=Wingdings><span lang=EN-US style='font-size:9.0pt;font-family:Wingdings'>à</span></font><font
size=1 face=Arial><span lang=EN-US style='font-size:9.0pt;font-family:Arial'>
MAC driver.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span lang=EN-US
style='font-size:10.0pt'>Yours sincerely</span></font><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span lang=EN-US
style='font-size:10.0pt'>Rudolph.Lu</span></font><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
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