From: Leon Romanovsky <leon@kernel.org>
To: Olaf.Krzikalla@dlr.de
Cc: linux-rdma@vger.kernel.org
Subject: Re: Understanding the allocation size of mlx5_alloc_buf
Date: Thu, 6 Jul 2023 19:47:48 +0300 [thread overview]
Message-ID: <20230706164748.GW6455@unreal> (raw)
In-Reply-To: <7f6a9b854205410eb45a665b1e84c0f2@dlr.de>
On Thu, Jul 06, 2023 at 12:48:46PM +0000, Olaf.Krzikalla@dlr.de wrote:
> Hi @all,
>
> creating connections via create_qp fails on our cluster for rather small numbers of processes (128 is working, 256 not) due to an out-of-memory error. I've tracked down the issue to an mlx5_alloc_buf call, which allocates ~500kB per call, which seems to be a lot.
>
> heaptrack tells me the following:
>
> 34.47M peak memory consumed over 92 calls from
> mlx5_alloc_buf
> in /usr/lib64/libibverbs/libmlx5-rdmav34.so
> 8.65M consumed over 16 calls from:
> create_qp
> in /usr/lib64/libibverbs/libmlx5-rdmav34.so
> mlx5_create_qp
> in /usr/lib64/libibverbs/libmlx5-rdmav34.so
> .
>
> Can anyone help me to understand, what causes a 500kB allocation in create_qp? Maybe it is some sort of a configuration issue, which I can handle somehow.
>
> Thanks for help and best regards
> Olaf Krzikalla
>
>
> System information:
> CentOS Linux 7 (Core)
> Linux 3.10.0-1160.88.1.el7.x86_64
Please contact your Nvidia support representative, you are talking about distro kernel
and not linux upstream.
Thanks
> CA 'mlx5_0'
> CA type: MT4123
> Number of ports: 1
> Firmware version: 20.33.1048
> Hardware version: 0
>
>
>
>
>
>
prev parent reply other threads:[~2023-07-06 16:47 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-06 12:48 Understanding the allocation size of mlx5_alloc_buf Olaf.Krzikalla
2023-07-06 16:47 ` Leon Romanovsky [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230706164748.GW6455@unreal \
--to=leon@kernel.org \
--cc=Olaf.Krzikalla@dlr.de \
--cc=linux-rdma@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.