<div dir="ltr">Dear Sir/ma'am, <div><p>I've created a DPDK bond with two slave interfaces, each capable of
1Gbps (mtu 1500 and both Full duplex). I'm using bonding mode 0 (balance
RR - round-robin). Theoretically, this should give me a 2Gbps link.
However, the bond interface only reports a speed of 1Gbps, and I've
noticed that one of the slave interfaces is never active.
Here's a breakdown of my setup and the issue:</p><p>Here's a breakdown of my setup and the issue:</p><ul>
<li><strong>DPDK Version:</strong> 21.11.9</li>
<li><strong>Bonding Mode:</strong> 0 (balance RR)</li>
<li><strong>Number of Slaves:</strong> 2</li>
<li><strong>Slave Speed:</strong> 1Gbps each, same MTU and each operating at full duplex.</li>
<li><strong>Expected Bond Speed:</strong> 2Gbps</li>
<li><strong>Observed Bond Speed:</strong> 1Gbps</li>
<li><strong>Problem:</strong> One slave interface remains inactive. Both slaves were active <em>before</em> calling <code>rte_eth_dev_start(BOND_PORT)</code>.</li>
<li><strong>Lcore Usage:</strong> Currently using 1 lcore. Tried with 2 and 3 lcores, but the problem remains.</li><li>Output of <b>rte_eth_bond_active_slaves_get </b>gives 1 implying only 1 slave is active at a time. </li></ul><div><p>I'm following the DPDK bonding example (specifically the port initialization) found here: <a href="https://doc.dpdk.org/api-17.08/examples_2bond_2main_8c-example.html" rel="nofollow noreferrer">https://doc.dpdk.org/api-17.08/examples_2bond_2main_8c-example.html</a>, ( for reference only I've used sample from 21.11.9 only )</p><p><strong>My Questions:</strong></p><ol>
<li>What could be causing one of the slaves to become inactive after <code>rte_eth_dev_start(BOND_PORT)</code>?</li>
<li>Is there a specific configuration or step I might be missing that's preventing the bond from utilizing both slaves in round-robin mode?</li>
<li>How can I troubleshoot this issue to determine why the second slave is not participating in the bond? Are there specific DPDK tools or logs I should be examining?</li>
<li>Are there any known compatibility issues or limitations with balance RR mode that could explain this behavior?</li>
<li>Could the number of lcores be related to this issue, even though I've tried multiple values? Is there a minimum or recommended number of lcores for bond mode 0 with 2 slaves?</li></ol><p>Thanks and Regards </p><p>Aman Thakur</p></div><p><br></p></div></div>