public inbox for passt-dev@passt.top
 help / color / mirror / code / Atom feed
From: David Gibson <david@gibson.dropbear.id.au>
To: passt-dev@passt.top
Subject: Weird timeout issue with passt
Date: Thu, 23 Jun 2022 15:59:20 +1000	[thread overview]
Message-ID: <YrQBOFWthrYYC31a@yekko> (raw)

[-- Attachment #1: Type: text/plain, Size: 1757 bytes --]

I alluded to this in my last patchset, but here's the information I've
gathered on the current problem I'm hitting running the passt distro
tests.  It's pretty weird.

On at least two occasions the tests have stalled during the Fedora 30,
aarch64 test, with the guest getting a timeout downloading the package
lists before installing new packages.  For me this is selecting the
mirror mirror.2degrees.nz.  I'm not sure which factors are are
relevant to reproducing the problem though.

* The problem seems to me that the download suddenly stops progressing
* partway through, causing dnf to eventually time out

* If I manually try a "dnf clean all && dnf makecache -v" using the
  same guest image, it  doesn't fail every time, but it fails
  significantly more often than not

* It doesn't fail on the same file every time

* I haven't been able to reproduce manually downloading the failing
  file with curl (tried repeatedly)

* If I restrict dnf to a single repository rather than the whole set,
  I haven't managed to reproduce the problem

* If I use qemu's -net user slirp instead of passt with the same disk
  image , I haven't been able to reproduce the problem (tried a bunch
  of times)

* I've reproduced with the guest using both IPv4 and IPv6

* I have reproduced what looks like the same problem with an x86 guest
  image under KVM (also Fedora 30), but it seems to happen much less
  often (seen once in 10 or more attempts)

* Seems to reproduce fairly readily with an x86 guest under TCG
  though, so I'm guessing the difference is timing related.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

             reply	other threads:[~2022-06-23  5:59 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-23  5:59 David Gibson [this message]
2022-06-23  9:32 ` Weird timeout issue with passt Stefano Brivio

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=YrQBOFWthrYYC31a@yekko \
    --to=david@gibson.dropbear.id.au \
    --cc=passt-dev@passt.top \
    /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).