yahoo-eng-team team mailing list archive
-
yahoo-eng-team team
-
Mailing list archive
-
Message #86706
[Bug 1937261] Re: python3-msgpack package broken due to outdated cython
** Changed in: cloud-archive
Status: New => Confirmed
** Also affects: cloud-archive/ussuri
Importance: Undecided
Status: New
** Changed in: cloud-archive
Status: Confirmed => Invalid
** Changed in: cloud-archive/ussuri
Status: New => Triaged
** Changed in: cloud-archive/ussuri
Importance: Undecided => Medium
** No longer affects: python-msgpack (Ubuntu)
** No longer affects: python-oslo.privsep (Ubuntu)
--
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to neutron.
https://bugs.launchpad.net/bugs/1937261
Title:
python3-msgpack package broken due to outdated cython
Status in Ubuntu Cloud Archive:
Invalid
Status in Ubuntu Cloud Archive ussuri series:
Triaged
Status in neutron:
New
Status in oslo.privsep:
New
Bug description:
After a successful upgrade of the control-plance from Train -> Ussuri
on Ubuntu Bionic, we upgraded a first compute / network node and
immediately ran into issues with Neutron:
We noticed that Neutron is extremely slow in setting up and wiring the
network ports, so slow it would never finish and throw all sorts of
errors (RabbitMQ connection timeouts, full sync required, ...)
We were now able to reproduce the error on our Ussuri DEV cloud as
well:
1) First we used strace -ffff -p $PID_OF_NEUTRON_LINUXBRIDGE_AGENT and noticed that the data exchange on the unix socket between the rootwrap-daemon and the main process is really really slow.
One could actually read line by line the read calls to the fd of the socket.
2) We then (after adding lots of log lines and other intensive manual
debugging) used py-spy (https://github.com/benfred/py-spy) via "py-spy
top --pid $PID" on the running neutron-linuxbridge-agent process and
noticed all the CPU time (process was at 100% most of the time) was
spent in msgpack/fallback.py
3) Since the issue was not observed in TRAIN we compared the msgpack
version used and noticed that TRAIN was using version 0.5.6 while
Ussuri upgraded this dependency to 0.6.2.
4) We then downgraded to version 0.5.6 of msgpack (ignoring the actual
dependencies)
--- cut ---
apt policy python3-msgpack
python3-msgpack:
Installed: 0.6.2-1~cloud0
Candidate: 0.6.2-1~cloud0
Version table:
*** 0.6.2-1~cloud0 500
500 http://ubuntu-cloud.archive.canonical.com/ubuntu bionic-updates/ussuri/main amd64 Packages
0.5.6-1 500
500 http://de.archive.ubuntu.com/ubuntu bionic/main amd64 Packages
100 /var/lib/dpkg/status
--- cut ---
vs.
--- cut ---
apt policy python3-msgpack
python3-msgpack:
Installed: 0.5.6-1
Candidate: 0.6.2-1~cloud0
Version table:
0.6.2-1~cloud0 500
500 http://ubuntu-cloud.archive.canonical.com/ubuntu bionic-updates/ussuri/main amd64 Packages
*** 0.5.6-1 500
500 http://de.archive.ubuntu.com/ubuntu bionic/main amd64 Packages
100 /var/lib/dpkg/status
--- cut ---
and et voila: The Neutron-Linuxbridge-Agent worked just like before (building one port every few seconds) and all network ports eventually converged to ACTIVE.
I could not yet spot which commit of msgpack changes
(https://github.com/msgpack/msgpack-python/compare/0.5.6...v0.6.2)
might have caused this issue, but I am really certain that this is a
major issue for Ussuri on Ubuntu Bionic.
There are "similar" issues with
* https://bugs.launchpad.net/oslo.privsep/+bug/1844822
* https://bugs.launchpad.net/oslo.privsep/+bug/1896734
both related to msgpack or the size of messages exchanged.
To manage notifications about this bug go to:
https://bugs.launchpad.net/cloud-archive/+bug/1937261/+subscriptions
References