public inbox for passt-dev@passt.top
 help / color / mirror / code / Atom feed
From: Jon Maloy <jmaloy@redhat.com>
To: passt-dev@passt.top, sbrivio@redhat.com, dgibson@redhat.com,
	lvivier@redhat.com
Subject: Problematic throughput numbers
Date: Wed, 25 Sep 2024 12:36:43 -0400	[thread overview]
Message-ID: <cb0a5320-12d7-4e0d-acee-2029b2fd89fa@redhat.com> (raw)

I made many runs with iperf3 ns->host, and the results are puzzling me.
Over and over again, I see throughput practically collapse, with a two 
orders of magnitude decrease.
Just to make sure this wasn't something introduced by me, I went back to 
the master branch and disabled the SO_PEEK_OFF feature.
The result was the same.
The below log shows typical run, but it is highly variable.
Sometimes almost the whole series is in the 50-70 Gb/s range, and 
sometimes almost all in the 100-300 Mb/s range.
When I added the kernel fix it didn't seem to make any difference.

To me this is really worrying, and should be investigated.

///jon




pasta NS->host (master branch, SO_PEEK_OFF disabled

-----------------------------------------------------------
Server listening on 5201 (test #2)
-----------------------------------------------------------
Accepted connection from 127.0.0.1, port 48354
[  5] local 127.0.0.1 port 5201 connected to 127.0.0.1 port 48360
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  7.61 GBytes  65.3 Gbits/sec
[  5]   1.00-2.00   sec  7.59 GBytes  65.2 Gbits/sec
[  5]   2.00-3.00   sec  7.55 GBytes  64.8 Gbits/sec
[  5]   3.00-4.00   sec  7.69 GBytes  66.1 Gbits/sec
[  5]   4.00-5.00   sec  7.55 GBytes  64.8 Gbits/sec
[  5]   5.00-6.00   sec  7.60 GBytes  65.3 Gbits/sec
[  5]   6.00-7.00   sec  7.52 GBytes  64.6 Gbits/sec
[  5]   7.00-8.00   sec  1.02 GBytes  8.73 Gbits/sec
[  5]   8.00-9.00   sec  3.50 MBytes  29.4 Mbits/sec
[  5]   9.00-10.00  sec  17.2 MBytes   145 Mbits/sec
[  5]  10.00-11.00  sec  64.0 MBytes   537 Mbits/sec
[  5]  11.00-12.00  sec  24.1 MBytes   202 Mbits/sec
[  5]  12.00-13.00  sec  25.4 MBytes   213 Mbits/sec
[  5]  13.00-14.00  sec  24.9 MBytes   209 Mbits/sec
[  5]  14.00-15.00  sec  21.4 MBytes   179 Mbits/sec
[  5]  15.00-16.00  sec  32.0 MBytes   268 Mbits/sec
[  5]  16.00-17.00  sec  10.9 MBytes  91.2 Mbits/sec
[  5]  17.00-18.00  sec  27.6 MBytes   232 Mbits/sec
[  5]  18.00-19.00  sec  75.6 MBytes   634 Mbits/sec
[  5]  19.00-20.00  sec  21.1 MBytes   177 Mbits/sec
[  5]  20.00-21.00  sec   109 MBytes   912 Mbits/sec
[  5]  21.00-22.00  sec  23.9 MBytes   200 Mbits/sec
[  5]  22.00-23.00  sec  62.6 MBytes   525 Mbits/sec
[  5]  23.00-24.00  sec  34.5 MBytes   289 Mbits/sec
[  5]  24.00-25.00  sec  54.4 MBytes   456 Mbits/sec
[  5]  25.00-26.00  sec  14.1 MBytes   118 Mbits/sec
[  5]  26.00-27.00  sec  38.8 MBytes   325 Mbits/sec
[  5]  27.00-28.00  sec  95.0 MBytes   797 Mbits/sec
[  5]  28.00-29.00  sec  23.2 MBytes   195 Mbits/sec
[  5]  29.00-30.00  sec  71.9 MBytes   603 Mbits/sec
[  5]  30.00-31.00  sec  28.8 MBytes   241 Mbits/sec
[  5]  31.00-32.00  sec  34.8 MBytes   292 Mbits/sec
[  5]  32.00-33.00  sec  19.4 MBytes   163 Mbits/sec
[  5]  33.00-34.00  sec  39.1 MBytes   328 Mbits/sec
[  5]  34.00-35.00  sec  31.4 MBytes   263 Mbits/sec
[  5]  35.00-36.00  sec  28.2 MBytes   237 Mbits/sec
[  5]  36.00-37.00  sec  48.5 MBytes   407 Mbits/sec
[  5]  37.00-38.00  sec  23.4 MBytes   196 Mbits/sec
[  5]  38.00-39.00  sec  71.4 MBytes   599 Mbits/sec
[  5]  39.00-40.00  sec  41.4 MBytes   347 Mbits/sec
[  5]  40.00-41.00  sec  15.2 MBytes   128 Mbits/sec
[  5]  41.00-42.00  sec  34.1 MBytes   286 Mbits/sec
[  5]  42.00-43.00  sec  31.1 MBytes   261 Mbits/sec
[  5]  43.00-44.00  sec  61.5 MBytes   516 Mbits/sec
[  5]  44.00-45.00  sec  38.2 MBytes   321 Mbits/sec
[  5]  45.00-46.00  sec  34.2 MBytes   287 Mbits/sec
[  5]  46.00-47.00  sec  33.8 MBytes   283 Mbits/sec
[  5]  47.00-48.00  sec  7.12 MBytes  59.8 Mbits/sec
[  5]  48.00-49.00  sec  97.4 MBytes   817 Mbits/sec
[  5]  49.00-50.00  sec  13.6 MBytes   114 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-50.00  sec  55.7 GBytes  9.57 Gbits/sec                  
receiver
-----------------------------------------------------------
Server listening on 5201 (test #3)
-----------------------------------------------------------


             reply	other threads:[~2024-09-25 16:36 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-09-25 16:36 Jon Maloy [this message]
2024-09-25 17:47 ` Problematic throughput numbers Stefano Brivio
2024-09-26  1:59 ` David Gibson
2024-09-26  3:45   ` Stefano Brivio
2024-09-26  3:50     ` David Gibson

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=cb0a5320-12d7-4e0d-acee-2029b2fd89fa@redhat.com \
    --to=jmaloy@redhat.com \
    --cc=dgibson@redhat.com \
    --cc=lvivier@redhat.com \
    --cc=passt-dev@passt.top \
    --cc=sbrivio@redhat.com \
    /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.
Code repositories for project(s) associated with this public inbox

	https://passt.top/passt

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 IMAP folder(s).