Re: [dpdk-users] How can create a mempool more than 20GB?

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 10 Sep 2019 19:02:37 +0800
宋捷 <songj@zctt.com> wrote:

> Hi All,
> 
>  
> 
>        I assigned 40GB hugepages for each node.
> 
> 
> 
>  
> 
>        I need a huge mempool buffer (20GB) for save received packets, I
> create a mempool as follow:
> 
> rte_pktmbuf_pool_create("rx_dump_pool",  8*1000*1000, 0, 0,
> RTE_MBUF_DEFAULT_BUF_SIZE, rte_socket_id() );
> 
>  
> 
> RTE_MBUF_DEFAULT_BUF_SIZE is 2048+128 , I think rte_pktmbuf_pool_create
> should create 8*1000*1000*(2176)≈16G buffer, 
> 
> But failed with below prompt:
> 
> EAL: eal_memalloc_alloc_seg_bulk(): couldn't find suitable memseg_list
> 
> EAL: eal_memalloc_alloc_seg_bulk(): couldn't find suitable memseg_list
> 
> EAL: Error - exiting with code: 1
> 
>  
> 
> I try to reduce the size, the mempool can be created successfully as follow:
> 
> rte_pktmbuf_pool_create("rx_dump_pool", 5000000, 0, 0,
> RTE_MBUF_DEFAULT_BUF_SIZE, rte_socket_id() );
> 
>  
> 
>  
> 
> Does DPDK mempool has a limited size ?  I have no ideal for this L
> 
>  

You are going to need 1G huge pages on this, and a system with very large
amount of memory. To setup 1G huge pages requires settings on kernel command line.

Also expect slow startup times with that much memory.