From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] config: reduce memory requirements for DPDK Date: Tue, 24 Jul 2018 14:03:08 +0200 Message-ID: <6155181.arAJIN2bNs@xps> References: <40cf48703f5fae8af8c31dcc8a1a1ecb0b151d27.1532426170.git.anatoly.burakov@intel.com> <7333019.QUcIvQh70r@xps> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, Ravi1.Kumar@amd.com, jerin.jacob@caviumnetworks.com, hemant.agrawal@nxp.com, yskoh@mellanox.com, arybchenko@solarflare.com, damarion@cisco.com, ktraynor@redhat.com, stephen@networkplumber.org, olivier.matz@6wind.com, christian.ehrhardt@canonical.com, bluca@debian.org To: "Burakov, Anatoly" Return-path: Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by dpdk.org (Postfix) with ESMTP id 2EB771DA4 for ; Tue, 24 Jul 2018 14:03:17 +0200 (CEST) In-Reply-To: List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 24/07/2018 13:04, Burakov, Anatoly: > On 24-Jul-18 11:23 AM, Thomas Monjalon wrote: > > 24/07/2018 12:03, Anatoly Burakov: > >> It has been reported that current memory limitations do not work > >> well on an 8-socket machines in default configuration when big > >> page sizes are used [1]. > >> > >> Fix it by reducing memory amount reserved by DPDK by default to > >> 32G per page size per NUMA node. This translates to allowing us > >> to reserve 32G per page size per NUMA node on 8 nodes with 2 > >> page sizes. > >> > >> [1] https://mails.dpdk.org/archives/dev/2018-July/108071.html > >> > >> Signed-off-by: Anatoly Burakov > >> --- > >> > >> Notes: > >> We could have increased CONFIG_RTE_MAX_MEM_MB but this would've > >> brought other potential problems due to increased memory > >> preallocation, and secondary process initialization is flaky > >> enough as it is. I am willing to bet that 32G per page size is > >> more than enough for the majority of use cases, and any > >> application with bigger requirements could adjust config options > >> itself. > > [...] > >> -CONFIG_RTE_MAX_MEMSEG_PER_TYPE=32768 > >> -CONFIG_RTE_MAX_MEM_MB_PER_TYPE=131072 > >> +CONFIG_RTE_MAX_MEMSEG_PER_TYPE=16384 > >> +CONFIG_RTE_MAX_MEM_MB_PER_TYPE=32768 > > > > Ideally, it should be a run-time option. > > > > It can be, yes, and this can be worked on for next release. However, we > also need to have good default values that work across all supported > platforms. Yes sure, we can wait the next release for a run-time option. How can we be sure these default values are good enough? It would be good to have several acks from various projects or companies.