-----Original Message-----
From: Ananyev, Konstantin
Sent: Tuesday, September 29, 2015 9:14 PM
To: Chen, Jing D; dev@dpdk.org
Subject: RE: [dpdk-dev] [PATCH 06/14] fm10k: add Vector RX function

quoted

+	/* A. load 4 packet in one loop
+	 * [A*. mask out 4 unused dirty field in desc]
+	 * B. copy 4 mbuf point from swring to rx_pkts
+	 * C. calc the number of DD bits among the 4 packets
+	 * [C*. extract the end-of-packet bit, if requested]
+	 * D. fill info. from desc to mbuf
+	 */
+	for (pos = 0, nb_pkts_recd = 0; pos < nb_pkts;
+			pos += RTE_FM10K_DESCS_PER_LOOP,
+			rxdp += RTE_FM10K_DESCS_PER_LOOP) {
+		__m128i descs0[RTE_FM10K_DESCS_PER_LOOP];
+		__m128i pkt_mb1, pkt_mb2, pkt_mb3, pkt_mb4;
+		__m128i zero, staterr, sterr_tmp1, sterr_tmp2;
+		__m128i mbp1, mbp2; /* two mbuf pointer in one XMM reg.

*/

quoted

+
+		if (split_packet) {
+			rte_prefetch0(&rx_pkts[pos]->cacheline1);
+			rte_prefetch0(&rx_pkts[pos + 1]->cacheline1);
+			rte_prefetch0(&rx_pkts[pos + 2]->cacheline1);
+			rte_prefetch0(&rx_pkts[pos + 3]->cacheline1);
+		}

Same thing as with i40e vPMD:
You are pretching junk addreses here.
Check out Zoltan's patch:
http://dpdk.org/dev/patchwork/patch/7190/
and related conversation:
http://dpdk.org/ml/archives/dev/2015-September/023715.html
I think there is the same issue here.
Konstantin

Thanks for the comments, Konstantin!  I'll check the material you referred to.