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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal">I have an application built with dpdk 17.11.<o:p></o:p></p>
<p class="MsoNormal">During initialization I want to change the mbuf size from 2K to 16K.<o:p></o:p></p>
<p class="MsoNormal">I want to receive packet sizes of 8K or more in one mbuf.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The VM running the application is configured to have 2G hugepages.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">I tried many things and I get an error when a packet arrives.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I read online that there is #define DEFAULT_MBUF_DATA_SIZE that I changed from 2176 to ((2048*8)+128), where 128 is for headroom.<o:p></o:p></p>
<p class="MsoNormal">The call to rte_pktmbuf_pool_create() returns success with my changes.<o:p></o:p></p>
<p class="MsoNormal">From the rte_mempool_dump() - “rx_nombuf” – Total number of Rx mbuf allocation failures. This value increments each time a packet arrives.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there any reference document explaining what causes this error?<o:p></o:p></p>
<p class="MsoNormal">Is there a user guide I should follow to make the mbuf size change, starting with the hugepage value?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Ed<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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