Re: [dpdk-dev] DPDK Max Mbuf Allocation

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 9/13/2021 5:56 AM, Kamaraj P wrote:
> Hello All,
> 
> Would like to understand or if there are any guidelines to allocate the max
> no of mbuf per NIC ?
> For example, if i have defined as below:
> #define RX_RING_SIZE 1024
> #define TX_RING_SIZE 1024
> 
> The Maximum RX/TX queues can be defined as 8 per NIC, What would be the max
> no of mbuf can be allocated per NIC ?
> Please share if there is any guildliness or any limitation to increase the
> mbuf ?
> 

Hi Kamaraj,

Max number of the queues and max number of the descriptors per queue depends to
HW and changes form HW to HW.
This information is shared by the PMDs that application needs to take into
account. For example the descriptor limitations are provided by
'rx_desc_lim'/'tx_desc_lim' etc.

After descriptor number is defined, testpmd uses the mbuf count as following,
which can be taken as sample:

nb_mbuf_per_pool = RTE_TEST_RX_DESC_MAX + RTE_TEST_TX_DESC_MAX + MAX_PKT_BURST +
                   (nb_lcores * mb_mempool_cache);




> Thanks,
> Kamaraj
>