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From: Stephen Hemminger <stephen@networkplumber.org>
To: amit sehas <cun23@yahoo.com>
Cc: "users@dpdk.org" <users@dpdk.org>
Subject: Re: rte_pktmbuf_alloc() out of rte_mbufs
Date: Fri, 22 Nov 2024 08:45:57 -0800	[thread overview]
Message-ID: <20241122084557.726e38e7@hermes.local> (raw)
In-Reply-To: <67781150.1429748.1732243135675@mail.yahoo.com>

On Fri, 22 Nov 2024 02:38:55 +0000 (UTC)
amit sehas <cun23@yahoo.com> wrote:

> I am frequently running into out of mbufs when allocating packets. When this happens is there a way to dump counts of which buffers are where so we know what is going on?
> 
> I know that each rte_mbuf pool also has per cpu core cache to speed up alloc/free, and some of the buffers will end up there and if one were to never utilize a particular core for a particular mpool perhaps those mbufs are lost ... that is my rough guess ...
> 
> How do you debug out of mbufs issue?
> 
> regards

The function rte_mempool_dump() will tell you some information about the status of a particular mempool.
If you enable mempool statistics you can get more info.

The best way to size a memory pool is to account for all the possible places mbuf's can be waiting.
Something like:
   Num Port * Num RxQ * Num RxD + Num Port * Num TxQ * Num TxD + Num Lcores * Burst Size + Num Lcores * Cache size

Often running out of mbufs is because of failure to free an recveived mbuf, or a buggy driver.

      reply	other threads:[~2024-11-22 16:46 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <67781150.1429748.1732243135675.ref@mail.yahoo.com>
2024-11-22  2:38 ` amit sehas
2024-11-22 16:45   ` Stephen Hemminger [this message]

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