Hi Wiles, Thanks a lot for your reply, I'm not sure what you said "tx flush threshold" exactly is. Is it in parameter of rte_eth_tx_queue_setup function to init tx queue? If so, it's configured as
static struct rte_eth_txconf tx_conf = { .tx_thresh = { .pthresh = TX_PTHRESH, // 36 .hthresh = TX_HTHRESH, // 0 .wthresh = TX_WTHRESH, // 0 }, .tx_free_thresh = MAX_PKT_BURST, // Use PMD default values, supposed to be 32 .tx_rs_thresh = MAX_PKT_BURST, // Use PMD default values .txq_flags = (uint32_t)ETH_TXQ_FLAGS_NOOFFLOADS, }; And the transmit ring size is 4096. As for network traffic, I use the http benchmark tool called wrk to perform stress testing for nginx, which running on my user-space TCP/IP stacks. I think the traffic is absolutely enough, and the issue occurs during the stress testing. Thanks again for your reply. Best wishes ________________________________ 发件人: Wiles, Keith <keith.wi...@intel.com> 发送时间: 2018年11月9日 15:37 收件人: Jiang Huiyou 抄送: dev@dpdk.org; Zhang, Qi Z 主题: Re: [dpdk-dev] rte_eth_tx_burst send packet fail when upgrade dpdk from 17.02 to 18.02 Sent from my iPhone > On Nov 7, 2018, at 2:36 AM, Jiang Huiyou <jhy19941...@hotmail.com> wrote: > > Hi, > My user-space TCP/IP stack works fine on DPDK 17.02, now I upgrade it to > 18.02. And then I use wrk http benchmark to test my stack, it work well > fine, but after a while, it couldn't send packet. I debug with gdb and find > the rte_eth_tx_burst always return 0, which means there is no available > transmit descriptor. And then I enable DPDK debug mode, the ixgbe_xmit_pkts > has been called to send packets (My NIC is Intel 82599ES 10G) and it called > ixgbe_xmit_cleanup to recycle used transmit descriptor, but > ixgbe_xmit_cleanup always return -1. The relevant code is blew. > Can you make sure the tx flush threshold? Some of the rx/tx rings were increased and if you do not have enough transmit traffic it can seem like it never does a cleanup. This is just guess try to make sure you have enough tx buffers allocated and rx as well. Hope that helps > /* Check to make sure the last descriptor to clean is done */ > desc_to_clean_to = sw_ring[desc_to_clean_to].last_id; > status = txr[desc_to_clean_to].wb.status; > if (!(status & rte_cpu_to_le_32(IXGBE_TXD_STAT_DD))) { > PMD_TX_FREE_LOG(DEBUG, > "TX descriptor %4u is not done" > "(port=%d queue=%d)", > desc_to_clean_to, > txq->port_id, txq->queue_id); > /* Failed to clean any descriptors, better luck next time */ > return -(1); > } > > I'm stuck here, and wonder how DPDK upgrade brings up this issue. Btw, there > was a similar mail which encountered the same issue, > http://mails.dpdk.org/archives/dev/2017-August/073240.html, but I find no > final solution for it. > > Thanks a lot for your time, and dying for your reply! > > Huiyou >