Hello Stephen,

Thank you for response, it helps me a lot. I understand problem better.

After reading mbuf library (
https://doc.dpdk.org/guides/prog_guide/mempool_lib.html)  i realized that
31 units allocation memory slot doesn't return to pool!

1 unit mbuf can be freed via rte_pktmbuf_free so it can back to pool.

Main problem is that allocation doesn't return to original pool, act as
used. So, after following rte_pktmbuf_free
<http://doc.dpdk.org/api/rte__mbuf_8h.html#a1215458932900b7cd5192326fa4a6902>
function,
i realized that there is 2 function to helps to mbufs back to pool.

These are rte_mbuf_raw_free
<http://doc.dpdk.org/api/rte__mbuf_8h.html#a9f188d53834978aca01ea101576d7432>
 and rte_pktmbuf_free_seg
<http://doc.dpdk.org/api/rte__mbuf_8h.html#a006ee80357a78fbb9ada2b0432f82f37>.
I will focus on them.

If there is another suggestion, I will be very pleased.

Best regards.

Yasin CANER
Ulak