From: Stephen Hemminger <stephen@networkplumber.org>
To: Alan Beadle <ab.beadle@gmail.com>
Cc: users@dpdk.org
Subject: Re: UDP Checksum offload with X550-T2
Date: Fri, 7 Feb 2025 14:52:11 -0800 [thread overview]
Message-ID: <20250207145211.175c4275@hermes.local> (raw)
In-Reply-To: <CANTAOdzQp7Gg4ipX0cQF=h4QYvPwkWOVqQziPpEViK4P4Egzmg@mail.gmail.com>
On Fri, 7 Feb 2025 17:34:47 -0500
Alan Beadle <ab.beadle@gmail.com> wrote:
> Apparently I just needed to increase the TX ring size. I'm still
> having trouble getting anywhere close to the theoretical 10 gigabit
> bandwidth of my NIC without running into TX failures. Should that be
> feasible with an MTU of 1514 bytes? I'm not even taxing the CPU very
> much now that checksum offload is working.
Remember that 10 gigabit includes all the other overheads like headers, inter-frame gap etc.
MTU is usually expressed independent of headers.
Interframe gap = 96 bits = 12 bytes
max frame size = 1518 bytes (Ether + MTU + CRC)
If you are using IP + UDP need to subtract those headers as well.
Which means 1500 becomes 1440 bytes.
With DPDK, the transmit cleanup is controlled via tx_free_thresh
which may need adjust as well.
prev parent reply other threads:[~2025-02-07 22:52 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-07 13:00 Alan Beadle
2025-02-07 13:44 ` Alan Beadle
2025-02-07 22:34 ` Alan Beadle
2025-02-07 22:52 ` Stephen Hemminger [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=20250207145211.175c4275@hermes.local \
--to=stephen@networkplumber.org \
--cc=ab.beadle@gmail.com \
--cc=users@dpdk.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).