From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerin Jacob Subject: [PATCH v2] mbuf: reduce pktmbuf init cycles Date: Tue, 27 Jun 2017 17:27:51 +0530 Message-ID: <20170627115751.4722-1-jerin.jacob@caviumnetworks.com> References: <20170605163807.31941-1-jerin.jacob@caviumnetworks.com> Mime-Version: 1.0 Content-Type: text/plain Cc: olivier.matz@6wind.com, Jerin Jacob To: dev@dpdk.org Return-path: Received: from NAM02-CY1-obe.outbound.protection.outlook.com (mail-cys01nam02on0078.outbound.protection.outlook.com [104.47.37.78]) by dpdk.org (Postfix) with ESMTP id E4A0B1F5 for ; Tue, 27 Jun 2017 13:58:34 +0200 (CEST) In-Reply-To: <20170605163807.31941-1-jerin.jacob@caviumnetworks.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" There is no need for initializing the complete packet buffer with zero as the packet data area will be overwritten by the NIC Rx HW anyway. The testpmd configures the packet mempool with around 180k buffers with 2176B size. In existing scheme, the init routine needs to memset around ~370MB vs the proposed scheme requires only around ~22MB on 128B cache aligned system. Useful in running DPDK in HW simulators/emulators, where millions of cycles have an impact on boot time. Signed-off-by: Jerin Jacob --- v2: - Removed RTE_PKTMBUF_HEADROOM from the memset area(Olivier) --- lib/librte_mbuf/rte_mbuf.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/lib/librte_mbuf/rte_mbuf.c b/lib/librte_mbuf/rte_mbuf.c index 0e3e36a58..ab436b9da 100644 --- a/lib/librte_mbuf/rte_mbuf.c +++ b/lib/librte_mbuf/rte_mbuf.c @@ -131,8 +131,7 @@ rte_pktmbuf_init(struct rte_mempool *mp, RTE_ASSERT(mp->elt_size >= mbuf_size); RTE_ASSERT(buf_len <= UINT16_MAX); - memset(m, 0, mp->elt_size); - + memset(m, 0, mbuf_size); /* start of buffer is after mbuf structure and priv data */ m->priv_size = priv_size; m->buf_addr = (char *)m + mbuf_size; -- 2.13.2