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dir="auto"><br></div><pre id="b" style="font-size: 13px; font-family:
monospace; white-space: pre-wrap; color: rgb(0, 0, 0);">Hi there,</pre><pre
id="b" style="font-size: 13px; font-family: monospace; white-space:
pre-wrap; color: rgb(0, 0, 0);">I'm developing a custom virtual switch
using OVS-DPDK(v19.11.10). In order to achieve 10Gbit/s, I modified the OVS
pmd mode from run-to-completion to pipeline. I used 1 thread as rx thread,
4 threads as worker thread and 1 thread as tx thread. it's a load balance
archiecture.</pre><p style="font-size: 13px; font-family: monospace;
white-space: pre-wrap; color: rgb(0, 0, 0);">I found the forwarding rate
can reach 10Gbit/s in first 2 minite, and then drop to 5Gbit/s . My traffic
generator keeps send packets at 10G rate. I debugged and found that packet
loss occurred in `rte_eth_tx_burst`, then it invoke `ixgbe_xmit_pkts_vec`
-> `ixgbe_xmit_fixed_burst_vec` , in `ixgbe_xmit_fixed_burst_vec`it
should be `txq->nb_tx_free` < `nb_pkts`, it means there is not
enough TX descriptor to be allocated.</p><p style="font-size: 13px;
font-family: monospace; white-space: pre-wrap; color: rgb(0, 0,
0);"><br></p><p style="font-size: 13px; font-family: monospace;
white-space: pre-wrap; color: rgb(0, 0, 0);">I have tried increasing
socket-mem when starting program and reducing the size of batch sent,
neither worked. I wonder if i am missing something important? This
question has been bugging me for weeks.</p><pre id="b" style="font-size:
13px; font-family: monospace; white-space: pre-wrap; color: rgb(0, 0,
0);"><br></pre><pre id="b" style="font-size: 13px; font-family: monospace;
white-space: pre-wrap; color: rgb(0, 0, 0);">Does anyone know this issue?
Thanks,
BR,
Yalou</pre></div>
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