From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <nhorman@tuxdriver.com> Received: from smtp.tuxdriver.com (charlotte.tuxdriver.com [70.61.120.58]) by dpdk.org (Postfix) with ESMTP id 3EBF1683A for <dev@dpdk.org>; Wed, 17 Sep 2014 17:24:18 +0200 (CEST) Received: from nat-pool-rdu-u.redhat.com ([66.187.233.203] helo=localhost) by smtp.tuxdriver.com with esmtpsa (TLSv1:AES128-SHA:128) (Exim 4.63) (envelope-from <nhorman@tuxdriver.com>) id 1XUHB1-0001MT-Sh; Wed, 17 Sep 2014 11:29:57 -0400 Date: Wed, 17 Sep 2014 11:29:45 -0400 From: Neil Horman <nhorman@tuxdriver.com> To: Bruce Richardson <bruce.richardson@intel.com> Message-ID: <20140917152945.GF4213@localhost.localdomain> References: <1410948102-12740-1-git-send-email-bruce.richardson@intel.com> <1410948102-12740-4-git-send-email-bruce.richardson@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1410948102-12740-4-git-send-email-bruce.richardson@intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Score: -2.9 (--) X-Spam-Status: No Cc: dev@dpdk.org Subject: Re: [dpdk-dev] [PATCH 3/5] testpmd: Change rxfreet default to 32 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK <dev.dpdk.org> List-Unsubscribe: <http://dpdk.org/ml/options/dev>, <mailto:dev-request@dpdk.org?subject=unsubscribe> List-Archive: <http://dpdk.org/ml/archives/dev/> List-Post: <mailto:dev@dpdk.org> List-Help: <mailto:dev-request@dpdk.org?subject=help> List-Subscribe: <http://dpdk.org/ml/listinfo/dev>, <mailto:dev-request@dpdk.org?subject=subscribe> X-List-Received-Date: Wed, 17 Sep 2014 15:24:18 -0000 On Wed, Sep 17, 2014 at 11:01:40AM +0100, Bruce Richardson wrote: > To improve performance by using bulk alloc or vectored RX routines, we > need to set rx free threshold (rxfreet) value to 32, so make this the > testpmd default. > > Signed-off-by: Bruce Richardson <bruce.richardson@intel.com> > --- > app/test-pmd/testpmd.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c > index 9f6cdc4..5751607 100644 > --- a/app/test-pmd/testpmd.c > +++ b/app/test-pmd/testpmd.c > @@ -225,7 +225,7 @@ struct rte_eth_thresh tx_thresh = { > /* > * Configurable value of RX free threshold. > */ > -uint16_t rx_free_thresh = 0; /* Immediately free RX descriptors by default. */ > +uint16_t rx_free_thresh = 32; /* Refill RX descriptors once every 32 packets */ > Why 32? Was that an experimentally determined value? Does it hold true for all PMD's?