From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olivier MATZ Subject: Re: RTE mempool "used count" steadily goes down to zero despite steady packet throughput Date: Mon, 01 Dec 2014 10:58:15 +0100 Message-ID: <547C3BB7.5010309@6wind.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Steve Noble , Ashish Juneja To: Kamraan Nasim , dev-VfR2kkLFssw@public.gmane.org Return-path: In-Reply-To: List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" Hi Kam, On 11/28/2014 06:34 PM, Kamraan Nasim wrote: > I have ~15Gbps of traffic flowing through two 10GE ports and been profiling > the rte mempool(or rather the pktmbuf mempool) memory consumption: > > I have per lcore caching disabled(cache_size is 0) > > I have noticed that: > - Mempool FREE cnt(as given byt rte_mempool_free_count()) increases > - Mempool USED cnt(as given by rte_mempool_used_count() decreases and > eventually drops to 0. When this happens, mempool reports itself as EMPTY > - rx_nombuf stats for the eth ports start climbing > - Valgrind Memcheck does not indicate any obvious leaks in RTE mempool or > my application. > > > I was wondering if others have come across this issue? Or if people here > have used ways, besides Valgrind to profile the mempool or the pkt mbuf > pool? First, be careful with rte_mempool_free_count(): it returns the number of free entries in the internal ring of the mempool, which actually corresponds to the number of allocated objects from the mempool point of view. See: http://dpdk.org/browse/dpdk/tree/lib/librte_mempool/rte_mempool.h If you have the number of allocated objects increasing, and the statistics rx_nombuf increasing when the mbuf pool is empty, it means that you have a mbuf leak in your application. Valgrind won't see it since it does not know about mempool alloc/free functions. Regards, Olivier