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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal">We got the following error when running systemd on a device with many ports:<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial","sans-serif";color:#333333;background:white"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial","sans-serif";color:#333333;background:white">"rtnl: kernel receive buffer overrun</span><span style="font-size:10.5pt;font-family:"Arial","sans-serif";color:#333333"><br>
<span style="background:white">Event source 'rtnl-receive-message' returned error, disabling: No buffer space available"<o:p></o:p></span></span></p>
<p style="mso-margin-top-alt:7.5pt;margin-right:0in;margin-bottom:0in;margin-left:0in;margin-bottom:.0001pt;line-height:15.0pt;background:white">
<span style="font-size:10.5pt;font-family:"Arial","sans-serif";color:#333333">I think the kernel socket receive buffer queue should be increased. The default value is taken from:<br>
"/proc/sys/net/core/rmem_default", but we can overwrite it using SO_RCVBUF socket option.<o:p></o:p></span></p>
<p style="mso-margin-top-alt:7.5pt;margin-right:0in;margin-bottom:0in;margin-left:0in;margin-bottom:.0001pt;line-height:15.0pt;background:white;orphans: auto;text-align:start;widows: auto;-webkit-text-stroke-width: 0px;word-spacing:0px">
<span style="font-size:10.5pt;font-family:"Arial","sans-serif";color:#333333">This is already done in networkd for other sockets.<span class="apple-converted-space"> </span><br>
For example, the bus socket (sd-bus/bus-socket.c) has a receive queue of 8MB.<br>
In our case, the default is 208KB. <o:p></o:p></span></p>
<p style="mso-margin-top-alt:7.5pt;margin-right:0in;margin-bottom:0in;margin-left:0in;margin-bottom:.0001pt;line-height:15.0pt;background:white">
<span style="font-size:10.5pt;font-family:"Arial","sans-serif";color:#333333">Increasing the buffer receive queue for manager socket to 512KB should be enough to get rid of the above error.<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Please find the patch attached.<o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-GB">Alin Rauta<o:p></o:p></span></b></p>
<p class="MsoNormal" style="background:white"><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black">Software Applications Engineer</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black">+353 (0) 87 101 8449<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black;background:white">Intel Shannon Limited</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><br>
<span style="background:white">Registered in Ireland</span><br>
<span style="background:white">Registered Office: Collinstown Industrial Park, Leixlip, County Kildare</span><br>
<span style="background:white">Registered Number: 308263</span><br>
<span style="background:white">Business address: Dromore House, East Park, Shannon, Co. Clare</span></span><span lang="EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p>--------------------------------------------------------------<br>
Intel Shannon Limited<br>
Registered in Ireland<br>
Registered Office: Collinstown Industrial Park, Leixlip, County Kildare<br>
Registered Number: 308263<br>
Business address: Dromore House, East Park, Shannon, Co. Clare</p>
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