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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">That’s what I thought, but experiments that Peter and I have done have shown that even with one RSS queue and using the SEPTun 1 process (separating RSS from
worker threads and using cluster_flow) that the packets are still sent to the wrong thread.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">So either the cluster_flow hash is being calculated before reassembly, or the kernel/NIC hash is influencing cluster_flow in some way.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Everything I’ve read, including source code, is along the lines of what you are saying. However, in practice it doesn’t work.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">-Coop<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Michał Purzyński <michalpurzynski1@gmail.com>
<br>
<b>Sent:</b> Wednesday, July 3, 2019 1:01 AM<br>
<b>To:</b> Nelson, Cooper <cnelson@ucsd.edu><br>
<b>Cc:</b> Peter Manev <petermanev@gmail.com>; Cloherty, Sean E <scloherty@mitre.org>; Eric Urban <eurban@umn.edu>; Open Information Security Foundation <oisf-users@lists.openinfosecfoundation.org><br>
<b>Subject:</b> Re: [Oisf-users] [EXT] Re: Packet loss and increased resource consumption after upgrade to 4.1.2 with Rust support<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">1. af_packet flow defragments before calculating hash<o:p></o:p></p>
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<p class="MsoNormal">2. cluster_flow ignores hardware hash and computes it on its own<o:p></o:p></p>
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<p class="MsoNormal">3. cluster_qm uses skb_get_queue_mapping() and gets an index of a queue from the hardware (so it uses the hardware hashing, although implictly)<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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