Thank yall for addressing this! On Wed, Aug 7, 2024, 12:50 PM Nick Rosbrook <[email protected]> wrote:
> ** Changed in: procps (Ubuntu Oracular) > Status: In Progress => Fix Committed > > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/2003027 > > Title: > fq_codel qdisc compiled but not enabled on 22.10 > > Status in Ubuntu: > In Progress > Status in procps package in Ubuntu: > Fix Committed > Status in The Noble Numbat: > Confirmed > Status in procps source package in Noble: > Confirmed > Status in The Oracular Oriole: > In Progress > Status in procps source package in Oracular: > Fix Committed > > Bug description: > [ Impact ] > Starting with Ubuntu 22.10, the default qdisc regressed to pfifo_fast. > This is due to a change we merged from Debian, removing systemd's > /usr/lib/50-default.conf file. pfifo_fast does not prevent bufferbloat > issues, severely degrading networking performance on Ubuntu systems. > > [ Test Plan ] > On an Ubuntu VM, check that net.core.default_qdisc is set to 'fq_codel'. > `tc qdisc show` should also confirm fq_codel is being used. > > halves@noble-vm:~$ sysctl net.core.default_qdisc > net.core.default_qdisc = fq_codel > > halves@noble-vm:~$ tc qdisc show > qdisc noqueue 0: dev lo root refcnt 2 > qdisc mq 0: dev enp5s0 root > qdisc fq_codel 0: dev enp5s0 parent :1 limit 10240p flows 1024 quantum > 1514 target 5ms interval 100ms memory_limit 32Mb ecn drop_batch 64 > > [ Where Problems Could Occur ] > Users relying on the default pfifo_fast qdisc could see different > networking behavior. > > [ Other Info ] > Instead of adding a sysctl.conf file, Debian has decided to change their > default kernel configs to use fq_codel. This has the disadvantage of being > "hidden" from end users, instead of being a queryable setting in e.g. > /etc/sysctl.d/, and all kernel documentation still refers to pfifo_fast as > being the default. > > Systemd's /usr/lib/50-default.conf file includes a lot of other > settings that are either overruled elsewhere (e.g. from procps) or are > entirely missing from our stable releases. Introducing a diff from > Debian to ship this file only for the net.core.default_qdisc changes > seems excessive, so having a dedicated place under procps where other > similar toggles are already present seems like the more appropriate > solution. > > -- > [ Original Description ] > fq_codel has been the default in ubuntu since #1436945 > > It is also now the default in debian. Somewhere between 22.04 and > 22.10 though, it stopped being enabled by systemd? (it used to be > enabled there via a sysctl), and thus 22.10 (I tried both ubuntu > server and ubuntu studio) doesn't have it on. I rather *immediately* > noticed this huge regression (I run my ethernet at 100Mbit, and thus > immediately saw 400+ms latency) - and I hope it can be fixed in the > next release? > > it can also be made the default via compiling it into the kernel as a > kernel default. > > Aggh! death to fifos! > > root@localhost:~# sysctl -a | grep qdisc > net.core.default_qdisc = pfifo_fast > > disc pfifo_fast 0: dev eth0 parent :1 bands 3 priomap 1 2 2 2 1 2 0 0 1 > 1 1 1 1 1 1 1 > Sent 5250 bytes 53 pkt (dropped 0, overlimits 0 requeues 0) > backlog 0b 0p requeues 0 > > To manage notifications about this bug go to: > https://bugs.launchpad.net/ubuntu/+bug/2003027/+subscriptions > > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2003027 Title: fq_codel qdisc compiled but not enabled on 22.10 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/2003027/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
